@волк and Rowi,
The entire problem is this:
1. a lot of turms have this problem,
2. some big mods opted to adjust only the .tga, making only the main (the big one and more "useful") deck compass correct. The one in the pannel, near the telegraf continues showing the wrong uboat head direction (GWX as an example)
3. To really fix it, you need to make what I said above. I too use wings3D, a very simple and powerfull 3d tool, but you need to learn with that old tryal&error way...It´s not possible to fix this bug with S3D only.
4. What Rowi said is also true...some compass are also off placed a bit, what is another problem, easily fixeable with S3D only.
5. I have all them fixed for all turms...but you know, we have a lot of version of turms on a lot of mods, so...