To fix textures on 1.7, you can go in to your FS25 files, grab the textureshader, and move it to the Monteith folder and that will fix it. However, 1.7 broke the custom crop calendar. That, unfortunately, is not a "move a file" fix. They did this in 22 with texture shaders. now they did it again in 25. You should be able to google FS22 texture shader fix and it will be the same process to fix for 25.
Viewing post in FS25 Monteith, IA 1X comments
https://www.twitch.tv/tonymif/clip/SuperDeadLouseMrDestructoid-19F3j_v-K9GULRjN?... here's a clip showing the file to move and where to move it to.