Hello,
I was trying to create a song in BBMO that has a Part 1 and a Part 2 that are at two different tempos. Is this possible?
Yes and no.
If you are able to write both beats using same quarter note length but in a way that they sound like they have different tempo 
Yes, this is possible 
If you just want to adjust single tempo value between song parts then that is not possible 
(not with BBMO nor BBM)
More to the yes part:
Say you have a beat of 4/4 where hihat goes every 8th note, bass drum on 1 and 3 and snare on 2 and 4. Lets call this part 1.
To make same beat in half time you can make it 8/4 with hihat on quarter notes, bass drum on 1 and 5 and snare on 3 and 7
Extra:
For half time and double time the BB has midi commands so if you have Midi Maestro or any other device that can send midi then you could just launch a fill and send the needed midi command 
For more complex tempo changes you either need to send the tempo with midi commands or use some more difficult math to figure the time signatures and note positions
2 Likes
Bummer that there’s not a simple solution, I get what your saying on changing the beats to get the effect, I’ll try that, thanks!