I didn't use a nightly build, used 3.7.1 BP build.
Please bear with me here, I don't have the first clue of what I'm doing here, so I'm trying to explain it as 'educated' as possible

So I followed the instructions very carefully laid out in the thread for how to debug with VS. I did everything to the letter, when I noticed that I'm actually using VS2013. Now I didn't panic because that tortoise thingy did actually create a 2013 project folder, so I said yaaay.
I built a solution in VS, 6 succeeded, 1 failed as predicted, because VS Express can't mess around with FRED2. Great. Now, here's where I got confused (which happens often):
A new exe popped up in the game folder, that had the same name as the BP 3.7.1 debug build, except it was missing the 'BP'. I didn't make much of it. So I opened up the launcher, configured it in proper debug mode (windowed mode etc), pressed f5 in VS, and then black screen. I alt-tabbed out, and I already got error msges before anything happened. I was guessing because it was using a different exe that it should have.
So here's what I did: I started everything again (tortoise, then VS). When VS completed the build solution the second time, I took the original BP debug build (exe), renamed it in the game folder to reflect the filename of the build that VS created, and vois la - the game started, and proceeded to the crashpoint that I originally wanted it to debug. I copied the call stack and that's what you see there on the last link I posted.
This whole thing doesn't make sense to me, as I have no clue how VS works and what it does to these builds when it's 'building a solution'. So I only deducted that the errors I was originally seeing were consistent with the issue that I'm not using the compatibility package, or the file is not in the right folder etc. So, I took the original, renamed it to the one VS built, and it worked.
What am I missing here? Does this not help in the end to debug the original appcrash that Tenebra first mission runs into with 3.7.1 BP build?