Found this in Evernote - presently researching though customer is on RDP to server so hunting and pecking my way to finding the file.
RX 6.7+
Problem / Description:
After applying the fix to get FRX running in a 64-bit OS - the drill down viewer launches but nothing displays and there is no error message.
Resolution:
Search for drildown.ini (NOTE: One l in drildown ) on the local machine. Open this file in Notepad, and check the AppSize setting. BE CAREFUL making changes in this file as you can cause more problems than you're trying to fix...but try setting the AppSize to say AppSize=0/0/640/464
Location of this file (Note: Change out {insertusername} for the name of the user on the PC)
C:\Users\{insertusername|\AppData\Local\FRx Software\FRx 6.7 folder