Tutorial 2: Custom tileset graphics

Step 1: create the tileset
To create custom graphics in your level, you need to first modify the existing tileset. It is provided in the customlevels folder in both Photoshop (custom level tileset.psd) and bitmap (custom level tileset.bmp) formats. If you have Photoshop, open the .psd and edit that, otherwise open the .bmp in Paint and edit that. If you're not ready to draw your own tiles from scratch, you can always re-color or edit existing tiles. When you're done, save it anywhere where you'll be able to quickly find it, such as on your desktop. Hint: In Photoshop, turn on the grid to 32x32 pixels-- it'll make editing a LOT easier. Important: Don't change the order of tiles, and don't edit the very first tile, because that's a special, reserved, invisible solid tile.

Step 2: import the tileset into Mappy
With your level loaded in Mappy, go to File->Import on the menu, and choose your tileset. It should replace the existing tileset. You should then go to, on the menu, MapTools->Useful Functions->Auto Set BG Transparency, otherwise you might get some magenta backgrounds around your tiles in the game.

Step 3: making tiles solid
If you created new tiles, such as some kind of new platform, you can make your new tile solid by double-clicking on it in the right-side window pane, then setting its User 1 value to 1. 0 means not solid, 1 means solid. Don't mess with the other user values (User 2, User 3, etc.) because they affect other stuff...

Next tutorial:
Tutorial 3: Advanced customization with the override file