Rich Text Suite v1.2.1. in Mendix 2.5.1 doesnt work
Using mozilla Firefox 3.6.12 I've added the Rich Text Suite 1.2.1 to a form and while loading the form the message appears : 'Bezig met laden van localhost'. Using the firebug console the following error appears : 'This.editor is undefined' (643 out of range 16). IE and Chrome don't work either.
I had the same issue. You should file a bug report I think.