I'm running all these versions on an old IBM Thinkpad. It takes about 15 seconds to start the IDE on mine.
edit: Try selecting "Run in terminal" at the prompt. See if the terminal window will show you what is wrong. Mine throws some Gtk warnings, then shows
Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
and the IDE pops up.