diff --git a/Cargo.lock b/Cargo.lock
index 7d7c355af..0879a4843 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4205,7 +4205,7 @@ dependencies = [
 [[package]]
 name = "opencadcodec"
 version = "0.6.0"
-source = "git+https://github.com/HakanSeven12/opencadcodec.git?rev=76d2a1c#76d2a1c66702d9aaf3ef8d4ff7dc06f4a025da82"
+source = "git+https://github.com/HakanSeven12/opencadcodec.git?rev=bff95f5#bff95f5115dd9cc0c4983ba890c32f890948dfed"
 dependencies = [
  "anyhow",
  "bitflags 2.13.1",
@@ -4228,7 +4228,7 @@ dependencies = [
 [[package]]
 name = "opencadgraph"
 version = "0.1.0"
-source = "git+https://github.com/HakanSeven12/opencadgraph.git?rev=f8bbf40#f8bbf40282bce73e7a24ef4f242adf7617d6608e"
+source = "git+https://github.com/HakanSeven12/opencadgraph.git?rev=9635ba7#9635ba7cdbf3b607548b1b2c30e2c10e2e2684d1"
 dependencies = [
  "opencadkernel",
  "serde_json",
@@ -4237,7 +4237,7 @@ dependencies = [
 [[package]]
 name = "opencadkernel"
 version = "0.1.0"
-source = "git+https://github.com/HakanSeven12/opencadkernel.git?rev=e13f37f#e13f37f88f4a24084aefceccca74a65500fec0ac"
+source = "git+https://github.com/HakanSeven12/opencadkernel.git?rev=6146d31#6146d31e7ea6f240538af760b91c8640054d7466"
 dependencies = [
  "cavalier_contours",
  "opencadcodec",
@@ -4248,7 +4248,7 @@ dependencies = [
 [[package]]
 name = "opencadkernel-constraints"
 version = "0.1.0"
-source = "git+https://github.com/HakanSeven12/opencadkernel.git?rev=e13f37f#e13f37f88f4a24084aefceccca74a65500fec0ac"
+source = "git+https://github.com/HakanSeven12/opencadkernel.git?rev=6146d31#6146d31e7ea6f240538af760b91c8640054d7466"
 dependencies = [
  "nalgebra",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index bbab9bf40..013ce24a4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,10 +34,10 @@ rfd = "0.17"
 clap = { version = "4", features = ["derive", "string"] }
 env_logger = "0.11"
 log = "0.4"
-codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "76d2a1c", features = ["serde"] }
-kernel = { package = "opencadkernel", git = "https://github.com/HakanSeven12/opencadkernel.git", rev = "e13f37f", features = ["acis", "offset"] }
-kernel-constraints = { package = "opencadkernel-constraints", git = "https://github.com/HakanSeven12/opencadkernel.git", rev = "e13f37f" }
-graph = { package = "opencadgraph", git = "https://github.com/HakanSeven12/opencadgraph.git", rev = "f8bbf40" }
+codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "bff95f5", features = ["serde"] }
+kernel = { package = "opencadkernel", git = "https://github.com/HakanSeven12/opencadkernel.git", rev = "6146d31", features = ["acis", "offset"] }
+kernel-constraints = { package = "opencadkernel-constraints", git = "https://github.com/HakanSeven12/opencadkernel.git", rev = "6146d31" }
+graph = { package = "opencadgraph", git = "https://github.com/HakanSeven12/opencadgraph.git", rev = "9635ba7" }
 dwg-thumbnailer = { path = "crates/dwg-thumbnailer" }
 flate2 = "1"
 image = { version = "0.25", default-features = false, features = ["png", "jpeg", "bmp", "tiff"] }
diff --git a/crates/ocs_plugin_api/Cargo.toml b/crates/ocs_plugin_api/Cargo.toml
index 58e17f2b9..2c35b554f 100644
--- a/crates/ocs_plugin_api/Cargo.toml
+++ b/crates/ocs_plugin_api/Cargo.toml
@@ -15,7 +15,7 @@ serde_json = { version = "1", optional = true }
 # Pulled in only by the `host` feature, which adds the `opencadcodec`-typed
 # `HostApi` runtime surface. The default crate stays dependency-free so engine
 # crates and external tooling can depend on the manifest/ribbon contract cheaply.
-codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "76d2a1c", optional = true, features = ["serde"] }
+codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "bff95f5", optional = true, features = ["serde"] }
 
 # Runtime IPC and serialization (host feature only).
 interprocess = { version = "2", optional = true }
@@ -39,7 +39,7 @@ serde_json = "1"
 serde = { version = "1", features = ["derive"] }
 cargo-lock = "11"
 # opencadcodec is scanned at build time to generate the embedded type registry.
-codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "76d2a1c", features = ["serde"] }
+codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "bff95f5", features = ["serde"] }
 
 [dev-dependencies]
 serde_json = "1"
diff --git a/crates/ocs_web_worker/Cargo.toml b/crates/ocs_web_worker/Cargo.toml
index 3da241eb1..75496a65c 100644
--- a/crates/ocs_web_worker/Cargo.toml
+++ b/crates/ocs_web_worker/Cargo.toml
@@ -8,7 +8,7 @@ publish = false
 crate-type = ["cdylib"]
 
 [dependencies]
-codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "76d2a1c", features = ["serde"] }
+codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "bff95f5", features = ["serde"] }
 bincode = "1.3"
 serde = { version = "1", features = ["derive"] }
 console_error_panic_hook = "0.1"
diff --git a/plugins/opencad-python/Cargo.lock b/plugins/opencad-python/Cargo.lock
index 007c79458..d731bf763 100644
--- a/plugins/opencad-python/Cargo.lock
+++ b/plugins/opencad-python/Cargo.lock
@@ -1264,7 +1264,7 @@ dependencies = [
 [[package]]
 name = "opencadcodec"
 version = "0.6.0"
-source = "git+https://github.com/HakanSeven12/opencadcodec.git?rev=76d2a1c#76d2a1c66702d9aaf3ef8d4ff7dc06f4a025da82"
+source = "git+https://github.com/HakanSeven12/opencadcodec.git?rev=bff95f5#bff95f5115dd9cc0c4983ba890c32f890948dfed"
 dependencies = [
  "anyhow",
  "bitflags",
diff --git a/src/app/command_driver/solid3d.rs b/src/app/command_driver/solid3d.rs
index caac03566..ccaa8de3c 100644
--- a/src/app/command_driver/solid3d.rs
+++ b/src/app/command_driver/solid3d.rs
@@ -486,6 +486,8 @@ impl OpenCADStudio {
             .iter()
             .map(|(_, entity)| entity.clone())
             .collect::<Vec<_>>();
+        // Group 294: a base point the user picked.
+        let picked_base = options.base_point.is_some();
         let options = sweep_model::sweep_selection_options(&selection, options);
         let pending = if profiles.is_empty() {
             None
@@ -496,7 +498,8 @@ impl OpenCADStudio {
         let mut consumed = Vec::new();
         for (handle, profile) in profiles {
             let result = path.as_ref().zip(options).and_then(|(path, options)| {
-                let record = sweep_model::sweep_record(&profile, path, options)?;
+                let mut record = sweep_model::sweep_record(&profile, path, options)?;
+                record.flags_294_296[0] |= picked_base;
                 let (_, _, closed) = kernel::acis::sweep_profile_geometry(
                     record.sweep_entity.as_ref()?,
                     record.sweep_entity_transform,
diff --git a/src/entities/object_data.rs b/src/entities/object_data.rs
index bb1bb7e95..3270bc545 100644
--- a/src/entities/object_data.rs
+++ b/src/entities/object_data.rs
@@ -315,7 +315,7 @@ fn history_operation_text(operation: &SolidHistoryOperation) -> String {
             value.base_face
         ),
         SolidHistoryOperation::Sweep(value) | SolidHistoryOperation::Extrusion(value) => format!(
-            "{}; sweep {}; path {}; direction {:.6},{:.6},{:.6}; draft {:.6}; scale {:.6}; twist {:.6}; align {:.6}; bank {}; intersections {}",
+            "{}; sweep {}; path {}; direction {:.6},{:.6},{:.6}; draft {:.6}; scale {:.6}; twist {:.6}; align {:.6}; align start {}; bank {}",
             history_base_text(&value.base),
             embedded_name(value.sweep_entity.as_ref()),
             embedded_name(value.path_entity.as_ref()),
@@ -326,8 +326,8 @@ fn history_operation_text(operation: &SolidHistoryOperation) -> String {
             value.scale_factor,
             value.twist_angle,
             value.align_angle,
-            value.bank,
-            value.check_intersections
+            value.align_start,
+            value.bank
         ),
         SolidHistoryOperation::Loft(value) => format!(
             "{}; cross sections {}; guides {}",
diff --git a/src/scene/model/solid_history.rs b/src/scene/model/solid_history.rs
index bca6763f6..e8a1598d5 100644
--- a/src/scene/model/solid_history.rs
+++ b/src/scene/model/solid_history.rs
@@ -651,7 +651,7 @@ pub fn extrusion_surface_data(
             path_entity_transform: value.path_entity_transform,
             is_solid: false,
             sweep_alignment_flags: value.align_option as i16,
-            align_start: value.has_align_start,
+            align_start: value.align_start,
             bank: value.bank,
             base_point_set: true,
             reference_vector: value.reference_point,
diff --git a/src/scene/model/sweep_command_model.rs b/src/scene/model/sweep_command_model.rs
index 5a9671728..142d78e4d 100644
--- a/src/scene/model/sweep_command_model.rs
+++ b/src/scene/model/sweep_command_model.rs
@@ -17,6 +17,24 @@ fn embedded_sweep_profile(entity: &EntityType) -> Option<(codec::entities::Embed
     }
 }
 
+/// The sweep path as the reference records it: a 3D polyline as a wire
+/// body, anything else as its embedded entity.
+fn embedded_sweep_path(path: &EntityType) -> Option<codec::entities::EmbeddedEntity> {
+    let EntityType::Polyline3D(value) = path else {
+        return embedded_path(path);
+    };
+    let points = value.vertices.iter()
+        .map(|vertex| [vertex.position.x, vertex.position.y, vertex.position.z])
+        .collect::<Vec<_>>();
+    let mut document = codec::entities::acis::SatDocument::new();
+    kernel::acis::append_polyline_wire(&points, value.is_closed(), &mut document).ok()?;
+    Some(codec::entities::EmbeddedEntity::Body {
+        // The 3D polyline object type.
+        type_code: 16,
+        acis_data: codec::entities::AcisData::from_sat(&document.to_sat_string()),
+    })
+}
+
 pub fn is_sweep_profile(entity: &EntityType) -> bool {
     embedded_sweep_profile(entity).is_some_and(|(profile, transform)| {
         kernel::acis::sweep_profile_geometry(&profile, transform).is_ok()
@@ -64,10 +82,11 @@ pub fn sweep_record(profile: &EntityType, path: &EntityType, options: SweepOptio
         base,
         operation_major: 1,
         sweep_entity: Some(sweep_entity),
-        path_entity: Some(embedded_path(path)?),
+        path_entity: Some(embedded_sweep_path(path)?),
         scale_factor: options.scale,
         twist_angle: options.twist_angle,
-        align_option: u8::from(options.align),
+        // 1 aligns the profile to the path; 2 only moves it to the path start.
+        align_option: if options.align { 1 } else { 2 },
         has_align_start: true,
         bank: options.bank,
         sweep_entity_transform,
@@ -100,12 +119,32 @@ fn placed_sweep_record(profile: &EntityType, mut record: SolidHistorySweep) -> O
             [0.0, 0.0, 0.0, 1.0],
         ],
     });
+    // The record's matrices are the source profile frame (at the base point,
+    // in the profile plane) and the frame it is placed in at the path start;
+    // the reference re-places the profile from them when it re-evaluates.
+    let (plane, _, _) = kernel::acis::sweep_profile_geometry(
+        record.sweep_entity.as_ref()?,
+        record.sweep_entity_transform,
+    ).ok()?;
+    let x_axis = glam::DVec3::from_array(plane.x_axis).try_normalize()?;
+    let normal = glam::DVec3::from_array(plane.normal()?);
+    let base = glam::DVec3::new(record.reference_point.x, record.reference_point.y, record.reference_point.z);
+    let source_frame = glam::DMat4::from_cols(
+        x_axis.extend(0.0),
+        normal.cross(x_axis).extend(0.0),
+        normal.extend(0.0),
+        base.extend(1.0),
+    );
     let mut moved = profile.clone();
     crate::scene::view::dispatch::apply_transform(&mut moved, &crate::command::EntityTransform::Affine(transform));
-    let (sweep_entity, sweep_entity_transform) = embedded_sweep_profile(&moved)?;
+    let (sweep_entity, _) = embedded_sweep_profile(&moved)?;
     record.sweep_entity = Some(sweep_entity);
-    record.sweep_entity_transform = sweep_entity_transform;
-    record.flags_294_296 = [false, true, true];
+    record.sweep_entity_transform = source_frame.to_cols_array();
+    record.path_entity_transform = (map * source_frame).to_cols_array();
+    // Group 294 marks a profile only moved to the path, not turned onto it.
+    record.flags_294_296 = [record.align_option != 1, true, true];
+    // The reference records its default mitred joint.
+    record.miter_option = 2;
     record.reference_point = Vector3::new(0.0, 0.0, 0.0);
     Some(record)
 }
@@ -135,7 +174,7 @@ pub fn swept_surface_entity(record: &SolidHistorySweep) -> EntityType {
             sweep_entity_transform: record.sweep_entity_transform,
             path_entity_transform: record.path_entity_transform,
             sweep_alignment_flags: record.align_option as i16,
-            align_start: record.has_align_start,
+            align_start: record.align_start,
             bank: record.bank,
             base_point_set: true,
             reference_vector: record.reference_point,