This past summer my son and I had some struggles at the place you mention. I referred to them in a trip report. Now, many months later, and with the inevitable softening that accompanies advancing age, I understand that our troubles came from over-thinking the portage route, expecting it to be more nightmarish than it really was. So we dutifully fulfilled the sacred prophecy and made the route more nightmarish by engaging in some good old panicky backtracking. We disregarded the obvious signs that we were, indeed, on the right track all along. I prefer to say "we" because "I" is just too lonesome a word when considering assigning responsibility for error. But yes, the two beaver dams were a conundrum because, to us, rank amateurs that we are (I still can't assert with manly confidence if the moose I encounter are men-moose or women-moose, and what the hell, they're just "moose", why all the retrograde obsession about gender!), the dams looked at least as old as me
Cool aerial shots, thanks for posting. As to your question about the Gammon down to the Bloodvein, the portages were all in good shape and I don't remember any real hardships there. Water levels were very low, which made the short carries often easier and allowed for some shortcuts. Wonderful country!