Issues with Forza Horizon mod tool

Hi,
i’ve been using your mod tool for years without trouble but somehow this morning, when i tried to modify some of my car setups, the program tells me the file is not valid/not usable in the livery editor (bc you need to use the livery editor to acess tune files).

The real issue is that none of my car setups files works anymore (they dont get recognize by the program) either on horizon1,2 or forza 4, while the others files do (liveries and vinyl groups).

I tried to uninstall and reinstall back the program and my saves but i havent been able to fix it.

Is the issue coming from me or the program itself? (server issue, etc)