Last night I bought into the Prison Architect alpha and I spent some time playing around today. It’s not really playable, to be honest: I found my orders being ignored rather often which meant I couldn’t get stuff built so my prisoners started rioting. I also had a lot of escapes; I didn’t really build my entrance way securely enough. Looking forward to losing a lot of hours to this once it is finished…
Left-click your entrance door, and select the staff only option (can’t remember the exact name) in the information that comes up on the right. That should stop (nearly all) escapes.
No use–they get knifes and start breaking it down, or they slip through when it opens to let a staff member through. I really needed two or three doors to get through to stop the latter.