Changelog

1.0.4

The load mass factor is a config slider now (0 to 5, default 2, 0 is vanilla). The hardcoded constant worked, but a game rebalance would have needed a rebuild to retune around.

Updated: Rebuilt for R.E.P.O. v0.4. The patched methods (PhysGrabCart.CartMassOverride, PhysGrabObjectImpactDetector.FixedUpdate) and every cart field the mod reads are unchanged in v0.4, so a recompile is sufficient and behavior is identical to 1.0.2 on the new game build.

Mass scaling is now load-aware. CartMassOverride adds twice the summed mass of items currently in the cart's tray, so an empty cart stays at vanilla 4 and a loaded cart scales proportionally with its payload. Replaces the old flat 6x multiplier, which over-weighted empty carts and under-scaled very heavy loads.
Dropped the persistent rb.mass change at PhysGrabCart.Start. That was leaking the mass bonus into weak-grab lifts, door collisions while coasting, and every other cart interaction where no one was actively pushing. Scope is now strictly "during an active push."
In-cart adhesion now only kicks in below vanilla's 1 m/s threshold (vanilla handles everything above), and skips items moving fast relative to the cart. Fixes thrown valuables snapping in mid-air over the cart and dropping straight down without their throw momentum.

Docs: added before/after comparison GIFs to README (control, back-and-forth, grab-and-spin, basic maneuver). No functional changes.

HeavyMass: scales cart Rigidbody mass and CartMassOverride calls. Loaded turn rate returns to roughly empty-cart feel.
LerpBoost: items sync to cart velocity every physics tick, including angular contribution. No more drift into cart walls on turns.