sorry for posting this thread once more, but from what I found in the forum the problems seem similar but not the same as I am having.
If I try to use the online version of the installer, the installation breaks down in the middle complaining about not being able to patch QT files.
Then I tried the offline version of the installer, which does not even start. The installer dies soon after starting without giving any error.
Does anyone know what is going on? Why such a bad quality on the installer?