I tried to use this tileset but I have been having troubles. I tried to search things again on Google but still no go. Only thing I could find are threads asking for tilesets and such...

My Problem this time is... That greenish-blue background (Blank space) seems to go on my map and just sticks out. I went to MS paint and changed that color into white (Blank/default space). But it seems to just not work for me.

Is there a certain function to fix this or am I just doing things completely wrong? I copied-pasted office.png into my tilesets (graphic) and everything seems to be okay but just when I place them on the map... They stick out so I can't place the interior objects without having those annoying green spots.

If this was answered before, I apologize... Just frustrated with this problem.

There are two processes you can follow.
The easiest one:
When you import a tileset into RMXP, you get a dialouge to choose a transparent and semi transparent color. Efter you hit OK, RMXP automaticlly makes the image into a png file with the desired transparency. If you for example take a bmp file and just copy it into the Tileset folder, it won't go transparent. Use the "Materials" window to import the tileset.

The not so easy one:
You could use a image editor such as "Microsoft Photo Editor" or "GIMP" or anything like that and make the image transparent there, and then just save the file into the Tileset folder. You can't use Paint to make it transparent as it don't have any support for transparent images. Unless you have Windows 2000.

Ah thank you very much. Didn't think it was necessary importing the files via Resource manager. I thought it was okay if I did it myself. Thanks a lot, this really helped me out