Override.txt doesn't allow all bitmaps to override. (v0.15)

[Gambit37]

I've been experimenting a little with the override feature and trying out some new graphics. I've tried doors, and they work fine. I have also tried to replace the explosion graphic with something else, but the game continues to use the internal graphic.

Am I missing something here?. Perhaps some parts of the override file are not yet applicable?

[George Gilbert]

Retired for V0.16