here is an idea for the machine you see behind Ben make up an add-on 3D printer attachment that can be just put on using aliment pins and magnets, using the A axis to run the extruder.
also have it so you don't need any special software.
have a relay out put to turn on the heater bed have it connected to a heat controller
everything could be controlled by writing a special post processor that will turn the heat bed on delay by how much time it needs to get to temp then start doing the print then at the end of the code have a macro call that turns the heat bed off and retracts the filament a little bit.
a laser add-on could also be done as well depending on the controller that the machine has (what is it)???