Well i have had Messenger Plus before on a different pc and it worked a dream .. however i changed my pc only bigger hard drive more ram etc .. Still windows XP and msn 7.5 .
So i install Messenger Plus as i did last time and set it up all how i like it but this time when i have multiple conversations in the same window, when i click between them the window gets smaller for some strange reason, untill its soo small i cant see or read anything
If so this is a known issue with windows blinds and tabs. To fix it you could add the convo window to wbs block list (i couldn't tell you how as i don't use it myself )