Thank you for using the forum.
I would recommend that you contact support for assistance at 1-800-821-2797. Since you have identified you are having issues with the patch it would be best to have support help to troubleshoot the issue. They should be able to identify the proper steps so that the patch installs easily and they can then help instruct you on installing the firmware as well.
I am sorry I am not able to assist you further.
I'm writing about WorkCenter 5665 with System Software 21.113.02.12. We're encountering problems upgrading to firmware 21.120.52.000 because when we try to install XSA_56xx08_Pre-upgradePatch.dlm through CenterWeb or through LPR, machine always prints a message where it says that this patch is not compatible with this machine... so we cannot upgrade firmware because we cannot first install the patch! What we can do in order to do solve this issue?