Qt Open source + MSVC++ 2008

[marcel]

Why don't Qt add the necessary info to the PATH variable during installation?
Why don't Qt add the QTDIR variable during installation?

That is really is to do. Practically it shouldn't take you more that 30 seconds to do it.

The reason why they don't add it because there is no installer for the open source version (only for the mingw compiled version).

Should I run "Qt 4.3.2 (Build Debug Libraries"?

Only if you need the debug libs. But, since you are just starting, it is a good idea to have them, because you might get curious about what happens under the hood.

How do I use this project generator thing?

qmake?
you can generate a vcproj from a pro file.

Do I have to download and install the Windows platform SDK?

no.