[EDIT: SOLVED] SYSTEM WINDOW NOT DETECTING TRANSPARENCY

I have a problem in RPG Maker 2003;
I've gone and edited and saved my nice sys1 window in MS Paint, colored the background a bright pink color easy to see... I open up the game, import it, select the pink color as the transparency, test the game... And there's that same pink color everywhere. I'm wondering if there's some sort of glitch or error I'm missing, any help is appreciated.

Things I've already tried:
-checked to make sure the image was saved as the correct file type of .bmp(if it wasn't, it usually shows up all black in game anyway)
-changed the pink color to a different color and set that different color as transparent
-edited in GIMP to double make sure the filetype and bit depth were correct
-reselected the original system image file to check if transparency worked then (it did)

Has anyone else had this repeated problem? Its rather frustrating...

author=Trihan
Have you tried saving it as png instead of bmp?

I just did- when I import the image it flashes the color transparent likes its supposed to, yet still doesn't work when I test the game.
Right now the temporary solution is to just entirely throw out transparency, and color the background color same as the window box, so at least it won't be noticed. Hopefully the game's graphics aren't glitched in some horrible way...


EDIT: Problem solved

the GIMP program was compressing the file and removing unnecessary colors, resulting in a smaller than 256 bit depth... I changed this in the 'Mode' settings and it works now.