I've been trying to pinpoint the problem on IRC with someone who has the same problem as you. Even sent one of my custom emotes to him, a friend added it and again he couldn't add it through the rightclick menu. Also compared systemspec (OS, additions to the OS, MSNM version, Plus! version and plugins), his was the exact same as mine. Yet i don't have the problem and he does. Then later on i went to test it on MSNM with one of the MSNM betatesters, we still couldn't find the problem.
I doubt it can be found in documents and settings, maybe in the registry..and even that i doubt. I will shortcut this with a MSNM betatester to ask where it could be. Once he tells me what he needs i'll post back, unless a MSNM betatester will reply first ofcourse
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