franklin, i think that, unwittingly, you chose a difficult bread for your
first attempt--rye doughs are notoriously temperamental to work with. if
your recipe contained a high percentage of rye flour (50% or more), then
it's possible that you overkneaded the dough. rye gluten is much more
fragile than wheat gluten, and gluten is what allows dough to rise. heavy
kneading is necessary to develop the gluten in a wheat dough, but can break
down the gluten in a rye dough. when this happens, the dough is sticky
rather than smooth and elastic--if your dough was indeed "gooey," as you
describe it, then most likely it was overkneaded. as a result, the gluten
might have been sufficient to sustain the inital rise and to respond to
the heat-boost you gave the shaped loaves, but evidently it was in an
extremely fragile state and was unable to recover from tiny surface
disturbance of removing the towel. it's also likely that the loaves rose
too much (or too long) during this last rise. despite what the books say,
they shouldn't double--if they do, they have nothing left for ovenspring.
try to catch them when they're just shy of doubled. any dough that
collapses from having its covering removed or from being moved or slashed
is dough that's overproofed.
my recommendations: knead only until the dough is smooth and resilient,
then STOP. don't use heat to proof the shaped loaves. it's not necessary,
and you get better flavor from long, cool rises. check them often during
the final rise. the loaves are ready when they're no longer shiny, when a
small poke retains an impression, and/or when they're not quite doubled.
have the oven preheated (start it after you set the loaves for the final
proof) so it's ready when the loaves are.
hope this helps!