I just installed this driver and sent over 30 jobs without failure. Make sure you are actually removing the driver after uninstalling your printer in Library>printers>PPDs>Contents>Resources and also check the en.lproj folder
My printer is on 061.121.224.11800 Firmware, which is the latest, you can get it here:
https://www.xrxgsn.com/admin/user/spar_release.ihtml
The SPAR Release code is: WC75xxSpar
Notes :
• When upgrading to 061.121.222.06500 or later from any release less than 061.121.222.06500, pre-upgrade patch 361372v1.dlm (found in the .zip file) may need to be installed before upgrading to this latest release. The pre-upgrade patch will retain the Default Scan Template settings that were made prior to loading 061.121.222.06500. If you upgrade to 061.121.222.06500 or later without loading the pre-upgrade patch first, the Default Scan Template settings will reset back to factory default at which point you will need to manually set the Default Scan Template to the desired settings