I used this guide and ran into an issue with the thieves guild. When doing the main mission to return the skeleton key if you talk to the ghost and he opens the "pilgram's path" for you, then you leave, the path will close and not open again. I did this without knowing, so I could keep the skeleton key for other quests. I returned later and couldn't get in (making it impossible to get the final thieves guild achievement). I used this video to get around it----
It works perfectly and I got the achievement. Thought maybe this could/should be added to the guide as a *note.
Again, as I posted before, great guide. Just wanted to throw this out there for people that run into the issue I had.