Hallo!
Going by exclusion....after hours of work and testing I found a mod to improve the game's vanilla cargo wagons that was in serious conflict, preventing the program from starting.
Turned that off (it's a pity, because it's interesting), everything fell into place and I was able to enjoy the improvements of TF2.
----> I advise those who are still having difficulty starting the game, to check that they do not have it among their activated mods.
Thank you all for your attention.
The mod I'm talking about can be found at this link:
https://steamcommunity.com/sha…iledetails/?id=2908795162
Mauri