OK. Mattn helped and now the model works in game. The scull is great.
See patch 1532361...
Unfortunately, I cannot get the rocket to draw nicely on the battlescape. The smoke obscures the whole model, or perhaps the scale is different than for the High-explosive rocket? No clue...
Some random remarks: The model and texture are quite large in terms of file size. I wonder why... The rocket looks somewhat shorter and more bulky than the High-Explosive rocket. It still seems to fit the launcher, so this is not a problem. However, it looks also some more like a bomb, or a nuclear guided missile than a bazooka rocket. But I know nothing about weapons... One more nitpick --- there is no hole in the bottom of the rocket, it seems sealed off.
Waiting for more --- especially the other incendiary stuff made in a similar style...