Sadly I must report that fitzsteve's recovery disk is not cooperating. Can anyone else here try making an .adf for me of their recovery disk?
It was also suggested that I just reinstall my firmware. I did so successfully, but there was no change in the settings. I still only see a maximum of 1.5MB FAST RAM.
If I am faced with no solution, do I just contact my retailer next? In this case, it was AmigaKit. Fortunately, the ACA500 appears to be back in stock.