Why can't I use tile sets with like blue and green and stuff in the background?

[tdogg427]

Why Cant i use resources with Green and blue in the background weather it be Tilesets of Charsets anything if it has green in the back my RMXP laughs at me. IT says 'ha-haha-hahahaha!!!! You cant useee iiiit haha-haha-ha-ha! Help please!

[Morris Lawry]

YOu need to make the character sets or whatever transparent or the program will say "not happening"

[tdogg427]

KK. Thanks