The assembly manual, page 10, says "If there is any problem with the measured voltages then you have GOT to investigate and find the problem before going any further!."
I did, and got +5.3V, and +3.7V, at the locations specified. Are these within spec? And, if not, what needs correcting?
I built according to section 4.3.1, with the LM317LZ on the Prog Rock board, not on the Synth board. I did screw up, however, and had to purchase a replacement LM317LZ.
My supply voltage is +9V