Simplify 3d has the ability to update firmware on the fly based on the machine used to print. I have selected the Printrbot Play model since that is what I am using. However, S3D is choosing to update my machine to option "RepRap (Marlin/Repetier/Sprint" Is that correct for this machine? Thanks for any help you can provide.
Well Simplify3D doesn't update your printers firmware. But S3D needs to know which firmware the printer is using to get the right Gcodes for communication. As far as I can see the Printrbot is a Marlin based firmware, so your settings are right.