You need to uninstall the older Qube components, and then install the newer ones. No data is lost during the uninstall/re-install.
Stop the worker service
If you want to avoid a reboot during the uninstall/reinstall cycle, you need to stop the Windows Qube Worker service. You can either stop this service with the Services utility, or at the command-line if you've open a cmd prompt as "Run as Administrator"
sc stop qubeworker
and then in the Task Manager->Processes, kill the process named "watchdog".
Uninstalling the Qube Worker
The only condition is that the Qube-core is uninstalled last. You can uninstall all other Qube components in any order.
The most common order is:
- uninstall the Qube worker
 - uninstalll all Qube jobtypes (maya, 3ds Max, etc)
 - uninstall the QubeGUI (if installed)
 - uninstall the Qube-core
 
Installing the Qube Worker
The only condition is that the Qube-core is installed first. You can install all other Qube components in any order.
The most common order is
- install the Qube-core
 - install the Qube worker
 - install the QubeGUI