Latest updates: https://bugs.winehq.org/show_bug.cgi?id=58552#c43
Carla offers experimental features supporting VST DLL direct usage via Wine similar to how Steam on Linux handles running Windows games.
Carla direct VST DLL usage works without the GUI offsets.
Carla VST.so converted by yabridge from VST DLLs have GUI offset bugs.
Thus it seems yabridge may be handling windowing behavior better left to Wine if possible.
Maybe whatever Wine internal windowing component that resolves the GUI offsets for direct DLL usage can be integrated to VST.so files so they may still be used without any other Wine runtime dependencies?
These latest tests help further clarify where the underlying faults may lie regarding bug reports against this merge.