Flag Warps

Sorry if I sound like an idiot here, but how do you use 'em?
I've found plenty of stuff on using side warps, but nothing on these.

Flags are covered in the KS Level Editor Manual, available for download here.

In short, Flag Warps make you warp when you enter a screen that has one; you don't need to use the Warp object in the screen, just choose the Flag to check and the warp coordinates in the manager or the World.ini. Shifts can turn Flags on and off.