Built right into the QubeGUI:
QubeGUI->Help->Qube Jobtypes: Cinema 4D (Win)
The "Net Unlimited" license should be installed on each machine rendering. From Maxon:
Every machine has to have a valid serial number. In the case of the command line call, this can even be the same on all machines. However, due to [Cinema4d's] network serial number check and [Maxon's] license agreement, you'll have to have a NET Unlimited serial number. You need to install the Full C4D suite including all modules on to every node and use one of your C4D permanent serial numbers as well. Since the CMD line is all that is used, the app is not actually launched and will not interfere with the network license checking.
It also may be necessary to launch Cinema4d to activate the license on each Worker machine with the user rendering, either qube proxy user (qubeproxy) or the submitting user as specified.