I have just started using Studio One and had a look through the manual but can't see the answer to my question.

How do I set the arrangement window to start from bar -4? I do this usually to insert a short MIDI not for every instrument to sync it all up so in 4/4 timing when it hits 0.0.0.0 everything will be in sync.

 

I'm not really sure to be honest. If I have to put something before the start I jjust move the time signature point a bit forward so all displayed bars will take into account that point as starting beat, although this won't change how those bars are named (1 5 9 and so on). If it helps you can also add a marker to the new start, and leave the original start marker few beats/bars before so you can use Start/End to export your track instead of selecting everything by looping it.
This isn't a proper solution, just a workaround.