Note: You should have an already existing Windows Live Messenger install before using this as Windows Live Messenger needs a few dependencies.
So, while I wait for a response on my Escargot development server error post, I decided to make a batch file which allows for multiple Windows Live Messenger installations. This project took me several hours.
Requirements before using:
curl (curl for Windows, once downloaded, extract curl and then add the bin folder inside the folder you extracted to your PATH. Also install the certificate included.)
unzip (UnZip for Windows, just install and add the installation directory to your PATH.)
Download: https://github.com/hypocracys/MultiMessenger/releases/download/1.0/MultiMessenger.bat
I would generally recommend using this tool for downloading vanilla clients to patch, since the Patched clients could be outdated in the future.
Have fun!
P.S: This was tested on a vista machine, if any problems should occur then please reply to this post.
P.S #2: The messenger versions are installed in %HOMEPATH%.