I have just downloaded the client setup file. I run it.. it downloads about 10mb?.. then disappears for a split second, reappears and just sits at 0kb downloaded with 0kb download speed.. then stops responding and crashes. I cannot for the life of me get past this point! The attached images are the best I can do at a crash report.
I kind of had a similar problem. What I did was did a search and completely eliminated all traces of GW2. Even the prefetch data that you may find in your temp folder or something. Then, I did not download the official 21.8mb or so setup file, I browsed around and found a gw2.exe that was 20.8mb or something around the internets. I ran it and that huge download text from the setup was gone and instead I got the bar that everyone else should've gotten. It crashed once more and I deleted that .exe and renamed the new .tmp file it created---into a new .exe with the same name.
then it worked magically.
"Can a loyal servant take a second master?" -Zhang Ren