This is going to be a compilation of oddly specific solutions to problems and questions I come across while modding. The main purpose of this entry is so that when I think "I remember this happened before, and I know I figured it out eventually...", I can actually find the solution again.

But please feel free to share it or suggest additions.

Windows
The ratio between straight and diagonal tiles is 1.5. If you have a straight tiling window mesh, and you want to turn it into a diagonal tiling window mesh, scale it 1.5 in X.

The distortion ratio of straight wallmasks is also 1.5. If you have scaled your diagonal mesh by 1.5, your straight wallmask will fit it without any modifications. You can even repo it.

Milkshape
When importing a GMDC mesh, Milkshape gives the error "ERR: Too many P1 sections for this implementation" This is caused by the mesh having too many groups for the UniMesh importer to handle. To fix this you need to split the mesh into two files and then import them one over the other. The simplest way is to open the mesh in SimPE, select groups in the Groups tab of the GMDC's plugin view, delete some groups, and then export the mesh. Obviously, make note of which ones you deleted so you can then exit without saving, reopen the mesh, delete the other groups and export part 2 of your mesh. After doing this, make sure to save your damn mesh as MS3D next time.

This error can also be caused by ridiculously long resource names - shout-out to trappingEP07LongWavy3t2-tm-trappingep6sideshort3t2-tm-trappingcitysidebraids3t2-tf-trappingxmsims71m2f-tf-xms.flora.meshhair071-tmhairrocker_tslocator_gmdc If this is the cause, just trim the resource name before exporting.

Depending on the item you could probably also export as OBJ and then insert the bone structure from a random EA mesh. This would save repetitive clicking.

Somewhere on MTS there's a post from wes snarking about how he wasn't going to fix that bug because no mesh needed more than 8 groups anyway, but it'd be an awful lot easier to fix transparency issues if people's meshes had more groups.

BHAVs
Error messages which make no sense for the node they were created by - such as "illegal data owner" errors when you're working entirely with literals - are usually caused by junk data in unused operand slots.