LipoToid, I understand that you wanted to use the button to directly link (or show) to the Plus! forums (PS: why didn't you say this directly in answer to MenthiX's post?, it could have prevented all the talking and replying
). If the button is indeed used to directly link to the official Plus! Live website, then yes you can use it.
If the button links to the forums (or shows another dialog which has to do with the forums) than rather not use the Plus! Live logo (might be confussing), but the logo from the forum itself.
Since you've adapted the UI of the program to use a treeview instead of buttons (good switch IMO), you could now change the tree nodes (+ - etc) into icons. You can use the "favicon.ico" files from the forums you included in that treeview for that.
For the Messenger Plus! forum this icon is found here:
http://shoutbox.menthix.net/favicon.ico
For MSNFanatic forum:
http://www.msnfanatic.com/favicon.ico
(though it needs some resizing)
For Mess.be:
you need to find a mess.be icon, since it doesn't seem to have a favicon.ico file.
EDIT (thanks to Dempsey): the main site has one though:
http://www.mess.be/favicon.ico
Maybe, after confirmation from Dwergs, you can use that one...
If used in this way, nobody (incl. Patchou) will have any problems with granting you permission to use the icons.
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