Let me give a final update.
After all my whining about the dysfunction of ManicMoose, unincognito was able to diagnose the problem with MM as installed in my BDP-pi as being caused by a bad micro-SD card. He did this with the BDP-pi in service mode, which is slick beyond belief! I must point out that this same micro-SD card had previously been given a clean bill of health by Bryston's US rep while he had my BDP-pi in his hands. I don't know what to make of that.
In any event, unincognito directed Bryston's staff to send me a new micro-SD card, which I assume will have a current version of MM actually installed (I haven't received it yet). In the meantime I bought a 16GB Sandisk micro-SD card at BB. I was able to flash it with the latest firmware, v.2.42. It has worked perfectly. MM 2.42 still has some quirks that are unresolved since at least as far back as 2.36, but it works without crashing.
My thanks go to unincognito for helping me with this.