ContactSay
Mocking
StealDP
^^ I have/had all of those, and they have worked fine for me. ContactSay only temporarly changes your display name to your contacts, then changes back. It uses your font however.
My guess would either be a faulty install of WLM, Plus!, or the script itself.
Your contact doesn't need anything except msn/wlm for any of those to work, so I have a feeling its an error on your end.
Try uninstalling the scripts that aren't working, and then go download them. But save them to your computer, and use the "Import" button in the scrips dialog in Plus!. Scripts, for me, seem to corrupt themselves with a direct install from my browser >_>.
Good luck
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