Having Messenger Plus! or not makes absolutely no difference in how you chat.
Messenger Plus! is not a replacement of MSN Messenger, it is a program which adds some more features, just like MSN added winks in MSN Messenger 7 and voice clips in Windows Live Messenger.
Messenger Plus! simply adds some more things you can do, it is absolutely no replacement for MSN Messenger. The only difference you see in Messenger is an added menu in the contact list and chat window and 3 more buttons in a chat window.
In fact, Messenger Plus! is simply a dead program which you can't run if you do not have Messenger.
The contact list is still the contact list.
Make sure you're talking about Messenger Plus! as found on
http://www.msgpluslive.net/ or
http://old.msgplus.net/
The reason why your contact list is empty has got absolutely nothing todo with Messenger Plus!.
As it sounds you may have downloaded and run some fake (and even malicious) thing. Never ever download something from somewhere else than the official sites.
Please provide us a screenshot of how your contact list looks like.
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