Okay:
To not install it, simple select "I refuse to install the sponsor program" when installing Messenger Plus!, here is an image to show you how to do this:
Okay, to remove it:
Go to Start > Control Panel > Add/Remove Programs, go down to Messenger! Plus, press "Remove", then you can select, "Uninstall the sponsor software without uninstalling plus!" (or along those lines
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). It will ask you to fill in a security code, do this, reboot your computer, and the adware will be gone
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.