The EZX10RF specification indicates a maximum of 30 links. I would suggest calling or emailing SHN support to see if that is still the maximum number of links which can be stored in a new EZX10RF device. Also what device will you be using with the SHN Utility for powerline communication, a PLC or EZSrve? If you have an EZSrve, the EZX10RF could send a message to the EZSrve which triggers a macro which controls a Scene/Group of Insteon devices. This arrangement would not have the 30 device link limit.
I have used the Utility to manually create links in my EZX10RF and several other SHN devices. It is not difficult a process. It will take time to write 80-100 link records one at a time. I would use the EZX10RF Set button to create the initial link with an accessible responder device. Then use that link record as a pattern for creating the remainder of the Controller link records required in the EZX10RF. Also each Responder device requires a link record be written in the Responder. The Utility works with devices containing a linear link database only. It cannot write link records in a PLC for example.