Not bad. Especially for a first go round. I'll give my opinions real quick. O's are offense and X's are defenders.
Floor spacing looks like it would be a problem though. I'm guessing the O1 & O5 action to start the play is a pick and roll. O4 being at the foul line clogs the O5's area to work with.
In fact if X4 is quick or the screen action is slow to develope he can actually jump the ball handler. Also the pass from O1 to O3 back to O1 seems like wasted time. Why not just have to screen and re-screen with O5?
Like I said its damn good for a first go round. A few tweaks and it looks like it might actually work on a court.
I came across a really good 4 Out Open Post Motion offense recently. I'll try re-create it through the playbook and post it here. It would work really well because it suits the five players you listed to a tee.