As PlatGEnWohl 'Pro' ill give you info.
Read official site:
http://engine.wohlnet.ru/about.php
Engine and editor Calls PlatGEnWohl (Or short PGE,PGW,)
Its fully compatible engine that can edit SMBX levels. (But editor better than in original smbx)
Also,'This is an free and open source game engine and toolkit which giving able to create games of platform genre.'
You can download latest versions of editor and engine There:
http://engine.wohlnet.ru/docs/_laboratory/ .
Tutorial (INSTRUCTIONS) That make
many people im, and another videos like trailer, you can see there:
For more info - check Official wiki:
http://engine.wohlnet.ru/pgewiki/Main_Page or ask mail developer - Wohlstand . (Or me if wohlstand offline)