Did you set up a GroupId in loot_template?

As i have not followed the modding scene for a long time i have no idea how things are going but i hope you have better tools these days than what was available back then.

BTW you can try wmo import-export script for blender. With current version you can edit doodadsets direct in blender. Vertex paint is another feature in the list. You can even set batch types for faces or make two-layered materials with this script. So if you're still interrested in wow modding and wmo editing in particular then you can check the latest version here.

Auto selection off is simple the way noggit did it in the past and I dont need the triangle cursor to exactly edit stuff....
Also there is vertics edit mode now, where you can even select vertics and move and angel them specificly so even this usecase is no longer a point. In my opinion to much features are not always good. Sometime less is more. Special if you are new to an Application and start to learn it.

So finally I can edit terrain in noggit and not in blender. Yay!

I think it's all about points of interests in database

For regular mounts you need to use spellvisual.dbc.

I gоt it wrong

So can I export second MOTV and MOCV for two-layered material? It would be very useful when making models where you need some smooth transition between two textures.
About water: didn't figured out how exactly info about transparency and uv-map is stored(I can mention that slime  liquids need to uw-mapping, but water works fine even without it). Also I tried to set material to regular diffuse material or to material with terrain type = 10 or 11(terrain type none and terrain type water) but it does nothing to my liquids so I don't know if it's really needed to have another material for water. But anyway I think that transparency and uw map stored in [heightmap] in first four bytes(height value is second four bytes) per vertex. Vertecies goes in column order. Same with tiles as I think(types in MLIQ chunk on wiki). Btw didn't actually figued out what a those types are. But they are defines which tiles will be filled with water and which won't. BTW maybe here in those types are actually two values(half of a byte for each)(wrong info. Seems that types are actually types. But if set second half of a byt to F then this water tile will not be filled)
Here is what I get just with hexing: