I noticed that the Linux build of VPUML runs quite sluggish compared to the Windows build and chalked it to the machine I was using the Linux build on since the machine was somewhat old.
However, I tried running the Linux build on a newer machine and the sluggish performance was still there so then I became curious.
I checked the Java version that was distributed with the Linux build and noticed that it was version 1.5.0_12, which is quite old. (The Windows build also uses the same Java binary version but it seems to run fine anyway.)
My Linux systems are running Ubuntu 9.04 so I grabbed their latest Java package, which gave me version 1.6.0_14. I then deleted (renamed) the java binary included in VPUML and created a link to my system’s java binary and now VPUML runs as smooth as the Windows build, even on my old machine!
This Java version also resolves the desktop effects problem.
I don’t know if this was already noted but I’d thought I’d share it here.