OK, I do not have a theory as to why you are needing a 2nd cycle start press. That does not happen on any of my machines and I don't remember a report of this before.
So let's start at the basics:
Mach version?
Win version?
Motion device?
MSM version?
Hum, I really don't know what would cause that....
under the "double checking category" -
Go to the mach3 dir, and run the drivertest.exe progam - that will run the mach3 PP driver - does that say successful etc after a bit?
If so then we know that you do in fact have the PP driver installed.