Thanks, all: Especially D. Doornbos.
Since "undiscovered resource" was on pg. 85 (84 being last posted by Distiller,) I deleted it and was able to print. Subsequently, I deleted each paragraph and the one illustration in turn, "saving as" on the fly. Finally, one paragraph's absence triggered a successful PDF. After saving the chapter as an MIF, then trying to clip the paragraph in from there, (no go,) I simply re-entered everything. Small paragraph, couple of cross references. Bang, Distiller went all the way to the final page. Granted this is a process which ought to become automatic. But the advice lubricated it. Much gratitude, ~ Don Spencer