Different textures on the inside and outside is hard.
It can mess up the floor
The way you do it is press m when in segment mode to paint only walls. That's the best way, except manually editing textures in the depths of the FPS Creator files.
Changing the sky... click on build game, search through all the options, I know it's one of them.
Music: I think there is a soundloop script, you'll have to look.
(Create an object, make it dynamic, browse for the script as the main Ai, it's called something like soundloop.fpi.
Weapons and items... try pressing enter while holding them in the editor.
Hope those helped.
E.D.
EldestDragon
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