Not thinking you'd need TGC's permission for the texture in your own game as long as it was FPSC or DBP. You couldn't post it for others with the texture, but you could release the new model that referenced their texture in the .fpe.
But with saying this, I find that the documentation here at TGC often changes to suit the need at hand.
Case in point:
Quote: "We are pleased to announce that there are NO license restrictions on FPS Creator."
and in the documentation:
Quote: "You must also ensure that the copyright of FPS Creator is clearly listed in your
documentation as follows:
This game was created using FPS Creator. Copyright 2005 The Game Creators
Ltd. All Rights Reserved. www.fpscreator.com"
So either there's no restrictions at all, or the only restriction is that your game has to list the engine. I guess it depends on how they feel at the moment.
So, as there's never any clear cut answers to anything around here. Your really better just making your own board and own texture and cut them out of the picture entirely to avoid any problems.