My current diagramming program of choice is yEd. It definitely has it’s quirks, but I haven’t found anything this powerful that is free.
I’ve been running it for a long time on Red Hat Enterprise Linux 6 (64 bit) and recently did re-installs of Fedora 17 and RHEL 6 because I got a new notebook–more on that in another post. I got some weird errors trying to install it using the sh script. I’m not sure how I was able to previously install it, but apparently my old system had some of the prerequisite packages to make it work without me knowing it.
All the details of the problem are at http://yed.yworks.com/support/qa/17 and is specific to 64bit systems. The short answer is that you’re best off downloading a zip of the jar file and running it from a command line.
1) Download the Java zip version yEd
2) Unzip the file
$ unzip yEd-3.9.2.zip
3) Run it
$ java -jar ./yed-3.9.2/yed.jar
Did anyone else find a way to make the sh installer work?