Supaplex Editor 2.50Free
If you want to make your own levels for Supaplex game, then Supaplex Editor is the right choice for you.
Supaplex Editor has options like special paint tools (open or filled box, selection and copying, etc.) editing the graphics and player information, and loads more. It works very well and it has online help to explain everything.
If you run Windows, this is the recommended editor for you.