I'm using the latest version of the engine, version 7.60, I think it was.

*check return value of game_load? game_load equals 268467760 as soon as the engine starts, I don't even have to use game_load for it.
--does the load fail outright? What exactly do you mean?
*check format of button function? A button can be any size, right? So why would this matter?
*function not declared prior to use? Every function I used has been declared before using it.
*superfluous while(key_any) wait(1); ? It doesn't matter whether this wait(1) is there or not, tried it already.
*save / load incompatibility with modified scripts / level (already mentioned)? I am aware of this, but the action doesn't work no matter what. Even if I loaded the game without modifying the script.

My entity is just a plain model, without any flags set. But when I first start the game, the action works. But when I try the action after loading with game_load, it doesn't work any more.