Download: hamswap.zip (1.79 MB).
HamSwap is a tool for backing up your Loonyland and Kid Mystic world files and copying over custom world files to the ones the game uses. Just copy and paste hamswap.exe into either your Kid Mystic folder or your Loonyland folder (same one mystic.exe or loony.exe is in). Before you run it for the first time, make sure all your world files are at their original so HamSwap can make backups. You can then restore the backups from within HamSwap at any time.
The file naming system HamSwap uses is simple. For Kid Mystic, world files are simply named with a .dlw extension. For Loonyland, world files are named with one of an .adv.llw, .boss.llw, .ball.llw, .survive.llw, or .bowl.llw extension depending on what type of world it is. This is to avoid confusion as to what type of world they are.
Included with HamSwap are some example addons. Thanks to Davedude for contributing example.dlw for Kid Mystic, a quick adventure with a few easy levels. For Loonyland, there's example.bowl.llw which I made, and example.boss.llw by Redbone (thanks!). These are placed in the Kid Mystic or Loonyland folder the first time you run HamSwap, and can also be found in the hamswap.vfs folder.
For those who are interested, this program was written in Tcl using the Tk library for the windows you see. Full source code is available in the hamswap.vfs folder, if you care to know how I wrote it. If HamSwap isn't able to detect whether you're using Kid Mystic or Loonyland (which it should, if you put it in the right place), pass it "km" or "ll" as a command line argument.
Thanks for using HamSwap, and enjoy!