NoNewTaleToTell: Both can worked around though, the first...well I can't remember how (keep running I think)
jimnorth: Eyup, that's one of the Kind Of Annoying ones, and yup, that's how you fix it! The guy you're running along behind stops at a window about 3/4ths of the way through, but if you keep on running he'll suddenly teleport ahead of you right at the very end. Took me until the third try to decide just to ditch him and figured that out. :))
I'm only about halfway through it at the moment, but hopefully I'll remember there's a need for key rebinding if I run into the other bug. Thanks for the heads up!
No problem, to keep it spoiler free I'll just say that it involves a key not working (either one of the QTE keys or the space bar) which causes you to fall and fail. You'll know it when you find it, and you can rebind the key almost immediately afterwards. Oh, if you weren't aware, there is a free Sleeping Dogs HD Texture Pack that you can download through Steam.