Interesting find I'll take a look at it and see what I can find out about this

EDIT: after playing this for a while here's what I can say

1. This game is hard I can't get past the 1st level (YET) 
2. The game has some of the paletes from SMB2 (japanese version)
3. the title screen as some glitches on it

so I think this could be a tech demo or a legit beta but i'll leave it to drx to determine what this rom is since i'm not experienced enough to know for sure