This is very strange. Being beta testers for Messenger Plus! we have to install the sponsor software aswell, and something like this happening is very strange indeed. I'm still honestly not convinced that it is Messenger Plus! that installed the adware on your system in the first place.
Like you said, you're "good" at computers, so then why did you install the sponsor in the first place? When it clearly explains what it is in the EULA.
(Sorry if I came across as rude in that last bit btw, I was just trying to prove a point).
Also:
I'm surprised nobody has offered this advice.
Download the latest version of Messenger Plus! from
http://msgplus.net/download.php and run the installer. Make sure that you
do install the sponsor software when doing this. Once installed, reboot your computer and go to Control Panel > Add/Remove Programs and un-install the sponsor.
