Howto setup RT on existing Windows server?

I need to install RT onto an existing Windows server.
The server already has the latest MySQL and Apache version running so I
can’t use the Windows installer which installs it’s own version of MySQL
and Apache. (correct??)

is it possible to use the main tar distribution ?
or is there a way to tell the windows installer version to use the
already installed versions ?

another thing I noticed: the windows installer does not work behind a
firewall using a proxy server (ISA Server) or are the links broken ?
getting exe files during install with size 0 ?

Any hint much appreciated!


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