Welp, it turns out end of June was too short of a deadline. Turns out I couldn't do 3 levels in 10 days.
To tide people over, have a level I just finished making for an NSMB2 level design contest.
https://www.dropbox.com/s/fn3dl0o1jf2vlvs/TRS_Contest.zip?dl=0 (replaces 1-1)
New deadline is...