You want it even smaller than the minimum size?!?
Then there is almost nothing to see... seems not much usefull...
Anyways, as NanaFreak said, the only way to do that is to edit the interface file responsible for making that window.
1) This interface file is Interface1.xml and you can get it by going to the Messenger Plus! Preferences > Customize > Skins > Extract Resources > ...
2) There you unselect all the checkboxes except
"Extract Messenger Plus! interface files and images", which must be ticked.
3) Fill in a temporary directory to save the extracted resources and press
"Export".
4) Close the export log which pops up and go to that temporary directory with Windows Explorer.
5) In that directory you'll find a subdirectory named
"Messenger Plus!", and in there you'll find the interface file
Interface1.xml.
6) Open that file in notepad and start editing it.
7) You only need the subsection <Window Id="EventViewer" Version="1"> and its parent sections. Remove everything else.
8) Next, you need to alter the <MinWidth> and <MinHeight> tags.
9) After you're done you save the file and copy it into a subdirectory named
"Interface" of your Messenger Plus! installation directory. (you must create that subdirecty yourself; it wont exist yet).
Note: the file can be named anything you want (eg: Interface1_EventViewer.xml). As long as it has the xml extension, is in that directory, saved as a unicode file and the xml sections in it are properly formatted, Plus! will read it and use it instead of the default.
10) Restart Messenger.
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