iniBuilds DOES have issues with the FSUIPC WASM, but not FSUIPC installed by itself without the fsuipc-lvar-module folder. We were trying to figure out if we had to also uninstall FSUIPC completely, or SPAD.next (which I don't have) or GSX Pro (that I do have). We were troubleshooting a lot of things. The commonality seems to be specifically the fsuipc-lvar-module folder in the community folder.
As far as the modules subfolder differences, the one from Dec. 6th has an Asobo_C152.hvar file that I did not have previously (maybe from installing the beta of FSUIPC?). The rest of the files look the same for date and size, just that one C152 file being different. I don't think that matters because both folders acted the same, whether the C152 file was there or not.
I found the FSUIPC7 for Advanced Users.pdf and I've been reading it. It mentions AppData\Local\Packages\Microsoft.Limitless_8wekyb3d8bbwe\LocalState\WASM\MSFS2024\fsuipc-lvarmodule\work for 2024. I have a C:\Users\Aaron\AppData\Local\Packages\Microsoft.Limitless_8wekyb3d8bbwe\LocalState\WASM\MSFS2024 folder, but I do not have a fsuipc-lvarmodule subfolder there. I only have fcr-embedded and inibuilds-aircraft-a300. Maybe because I'm not actually using it so it's not creating those files and folders?
I have tested with a completely blank community folder and only the inibuilds-aircraft-a300 and fsuipc-lvar-module folders in my community folder under 2024. If both are there, the sim locks up with cold and dark start of the A300. If fsuipc-lvar-module is removed, it does not.
I have not tested under 2020 because I bought the "A300-600R Premium for MSFS 2024", it's native to 2024 and I don't own the older 2020 version. I don't know which specific versions others might be using though.
Hope that helps!