When I start the modpack it only opens vanilla minecraft. But when I exchange the modpack.jar file with one from another 1.12.2 modpack it works. That could be a work around but I want to have a new forge version and know which version it is exactly. Because I couldn't start the forge-universal file to extract it I just took it as modpack.jar as someone in the official guides comments suggested. That could be the problem.
Modpackside:
https://www.technicpack.net/modpack/minecolonies-plus.1689028
Not Working:
http://37.120.179.165/public/Technicpacks/MinecoloniesPlus/MinecoloniesPlus-0.0.1.zip
http://37.120.179.165/public/Technicpacks/MinecoloniesPlus/MinecoloniesPlus-0.0.2.zip
http://37.120.179.165/public/Technicpacks/MinecoloniesPlus/MinecoloniesPlus-0.0.3.zip
Working:
http://37.120.179.165/public/Technicpacks/MinecoloniesPlus/MinecoloniesPlus-0.0.4.zip
thanks in advance, jolo