[leonid]

I used very low bpms in Eyes of June to prevent the players from accidentally hitting mines or arrows that are supposed to be fake. You can put notes very close to the receptor and not affect the players if you set the bpm low (like -10 ~ 10), but if you use it too soon, the timeframe will go beyond the start point and will do funny things (which you probably don't want)

Also, when you do negbpm skip, be sure to skip at least an entire measure, and do not put any notes or mines in areas being skipped. Otherwise it will not work for some versions of stepmania. (for example, 4.0, openITG)

BPM180          BPM-50  [fake]   BPM50 [skipped] BPM180
--m10-------------m11--------------m12-------------m13-------------m14
   |   Some notes  | Put fakes here |  Keep empty   |   Some notes  |
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