I'm having a bit of trouble with transparency. I've created a tile set with a doorway. Just a simple black doorwate. Two four tiles black with the top arched. When I use the tiles on the map it shows up with like a black square around it. Not sure why, nothings visible in the psd file. I've saved as png both interlaced and non. Also tried the tiles on all three layers. It's not really making any sence..lol.

If the image itself already has transparency set there shouldn't be a problem, but clearly something's not working properly so you should take the long way around.

When you import the image in RPG maker (F10), it'll ask you to specify the transparent (and semi-transparent) color.

All transparent portions of the image will default to black, and so you would just choose the black as the transparent color.
Unfortunately it seems like you've got black parts for the actual doorway, so you might run into some problems there. Maybe the engine is having problems auto-determining the transparent color.

I think It had something to do with my import method. I had imported my tileset into the folder. Opened in photoshop, and was saving it, sort of a real time edit thing. I think RM had a problem with that, lol. I had to go into the database, erase the tileset fields, take it out of my project folder, and reimport, and set up after I touched it up...lol. Not sure whats up there.