I would assume your Plugins are to old and no longer compatible with current OS/Xojo Versions.
GuancheMOS f.e. got it’s last update in 2008, correct? And the other one is even older.
I think you should contact the developers of those Plugins and ask them about compatibility with current OS/Xojo versions.
[quote=166295:@Nicola Messina]ok, I’ll try to contact the developers, but the plugin on windows work perfectly!
Why not work on OSX?[/quote]
Nicola, I guess the plugin only include the Windows part, or maybe as Markus said, it includes the Carbon target for Mac but not the Cocoa one. And Carbon is no longer supported on Xojo (as well deprecated by Apple).