After getting 'Andreas' explicit permission to take over his code -- there is plenty of work before it can be useable.
I implemented private messaging on the site I oversee. Andreas's code pointed me to the right direction to begin my project, especially since I was new to Vbulletin source and methods back then.
Unfortunately, my team modifies vbulletin source directly and the hooks were not present in the vbulletin source then to make a workable mod.
In Andreas's code, the basis for the project is there, but there are many areas of the project that are incomplete as noted by the BETA status.
If someone decides to write a similar mod from the ground floor up and donate it to the community, then you are welcome to contact me for some pointers and pitfalls that I ran into. Have fun!
-- General shout-out to Andres: We miss you around here bud!