Hi ilkertezcan,
1) It's no bug, I'm going to remove support for WinNTSetup_x86.exe running on x64 OS.
Reason: There are some API's that can not work in WoW64 emulation,
I though i could find a good solution, but it would just makes thinks to complicated.
Also there is an faster x64 version available, don't know why sp many people want to run the x86 version.
2) Good, will add it to help.
4) Not so sure I like to add that.