(Re-)Installing Qt / Problem with debugger

[Computer Hater]

Hi,

I installed Qt about half a year ago. Initially, I had installed Eclipse, Wascana, MSys, MinGW and Qt separately in a bit of a seesaw of reinstalls, but eventually settled on just installing the complete Qt SDK for Windows and no non-Qt tools. (I'm using Windows Vista Home Premium on a Laptop.)
I also accidentally *replaced* the contents of the Windows PATH variable during Qt installation with the Qt PATH instead of appending to it. I tried to fix this by doing a system restore, but it didn't change anything. The OS as well as Qt seemed to be working fine, so I let it go. I don't know if this is relevant.

I've since been working with this Qt installation without any problems, until a few days ago I ran into a problem that made me want to use the debugger for the first time.
When I tried to debug, I received the two error messages in the attached screenshot simultaneously.

At first I only looked at the main directory given ('C:\Develop\Qt\') which was the one I used in my early installations, whereas the current one only uses 'C:\Qt\2010.05\'. So I figured that the debugger was expected to be in an old installation path and therefore couldn't be found.
I then did a reinstall, this time also selecting the 'post-mortem debugger' option.

While doing the reinstall, I stumbled on another problem. In the installation instructions, it says:

>>
Step 4: Build the Qt Library

To configure the Qt library for your machine, type the following command in a Visual Studio command prompt:
C:
cd /D C:\Qt\4.7.2
configure
...
>>

But I don't have Visual Studio AFAIK and trying the above in a DOS Shell doesn't work as the 'configure' command is said to be unknown.
I've then been told that 'configure' is a Unix command and I vaguely remember typing this in the MSys Unix shell during the earlier installations, but I'm not sure anymore how or if I did this for the current installation of Qt that I've been using and that has been working so far.
Now I wanted to do this properly, but couldn't follow this instruction.

I then realized that the Qt installation still worked even though I didn't complete the instructions. However, the debugger problem still persists. (Actually, I only tried compiling for the 'Debug' version instead of the 'Release' version after the reinstall, but I don't suppose that changes anything.)
It seems a similar problem with the debugger was discussed here.
But before I try anything else I would like to know how to run the 'configure' command under Windows to properly finish my reinstallation.