I'm working on a piece that was laid down by someone who left a measure out of the song. I need to insert it. Is there a command that will put it in and move all the time signature changes back? This is a midi track.

I'm sure there are lots of ways of doing this ... a simple way in a new midi track
1. create a 1 measure file maybe a 4 beat click track.
2. Move the midi track you have so it starts on measure 2.
3. move the measure created in step 1 to the 1st measure that you made room for in step 2.
4. Maybe remove the 4 beats you put in step 1
 
hope this helps
 
rafone

I would do something a little different.
 
Position the cursor where you want the measure inserted.
 
Select All (ctrl + a)
Project > Insert Time/Measures
 
The method suggested in the post above will not move any existing key, tempo or markers.