I am creating the search help transaction ZXF4 in our system. Since we are using our own namespace /xxxx/, both the transaction ZXF4 and the program ZGUIXTF4 have to be renamed. Is this possible?

Yes, you can rename both. Please put a command

ProcessingOption  SearchHelpTransaction="/xxxx/ZXF4"
into the session script (esession.txt).

The program ZGXUIXTF4 can be given any new name you want, e.g. /xxxx/ZGUIXTF4.