I had a similar issue when I installed it a couple of weeks ago but I didn't re-download. EDIT: my bad memory. Actually, it passed integrity check but failed multiple times during the actual installation.

I temporarily disabled the Microsoft Security Essentials real-time protection. However, I have been encountering frequent crashing so I ran memtest86+ and it found a bunch of errors with my memory. I swapped the memory modules around and it seemed to fix things. Maybe that was the real reason the installation failed. However, yesterday, again, PoE was frequently crashing. So I don't know. I live in a country where hardly anyone knows a second language unless it's part of their heritage, let alone knows it well enough to post a question to a forum. So I reckon you are doing well there :)