I'm using RapidMiner under Linux (Kubuntu Lynx). From the beginning on, the user interface was slow.
As it turned out, the standard-java installed was OpenJDK 6.
As soon as I installed Sun Java 6, the interface was fast as hell, and some bugs that had been bugging me for days simply vanished.
So, it seems like a good idea not to use any non-Sun Java to run RM.
thank you for this hint and for enduring the problems you had to endure during these days
Greetings,
Sebastian