Black interiors in Wazzal II

[Enet4]

Basically, I get this when entering the bunker in Errxelz 8:

Objects and creatures are pitch black, as if nothing but the alpha channel was considered except for the lighting objects.

Then I tried entering the Wolf IV, and the outcome appears to be the same:

The map looks fine on the editor:

[verhoevenv]

I can reproduce the bug on Ubuntu, but interestingly, this doesn't happen on Windows. The inside of the bunker is shown correctly for me.