Thanks!
Based on the schematic and board layout, I rebuilt the pro nRF shield on a pro proto shield.
No short this time, but I ran into the following issue when running the transmitter and receiver sketches provided in
http://digistump.com/wiki/digispark/tutorials/pronrf. Both pin 1 LEDs remain lit steadily. According to the documentation, this means that the transmitter/receiver are having trouble talking to each other. I tried powering up first the transmitter, then the receiver. I also tried powering up first the receiver, then the transmitter. Neither combination worked. Next, I'll likely try to use the keyboard library to perform debugging, unless someone has seen something similar before.