if you got a file called by the format. MMip then just put it in a folder to keep it in for storage and double click it with the left mouse button monkey will or should start for you and show you a panel that says install, click okay and it will be installed for you.

same thing with skins when you get them most are mmip files mmip = mediamonkey install package

I downloaded duplicate report 3.0 but I dont know where to put it.. i also downloaded some other scripts