okay, tl;dr on how to get micromania on DE:
1.Download the .scx file from the attached zip or get your own
2.put it in
c:\Users\<your username>\Games\Age of Empires 2 DE\<your steam ID>\resources\_common\scenario\
the folder for your steam ID should be already there, it usually starts with the digit '7'
Also, while testing it became kinda apparent to me that the pathfinding still needs a lot of work but.. oh well, maybe we'll get there eventualy