I loaded Meta via vdf, read my single post linked upper, but via gameinfo, the problem is still on.
I figured out!
Started unloading the plugins one-by-one, and after I removed the TF2_Equipment Manager plugin (
http://forums.alliedmods.net/showthread.php?t=98651) the AddOns are back, and can use all the functions of SM modification in the Players window. I posted a reply in that topic, waiting for the answer.