In reference to the following:

Novell Documentation

I need to replace my 512bit certificates with 1024bit or greater certificates. I don't see a problem doing this on my Primary and Satellite servers, but will my managed device agents stop communicating once I replace the certificates on the Primary and Satellite servers?

If my managed devices will keep communicating then I can build a bundle to script the following:
zac unr -f
zac cc
delete <ZENworks_installation_directory>\Novell\ZENworks\ cache\zmd\ /s
zac reg https://SERVER.FQDN:443

This would be a big problem if I have to manually do this to all of my users machines.