I'm showing the systray using Destruction.
I didn't get an arrow to cycle through the icons until i went to builder mode and opened properties on the sytray. started changing the distance between task size and the arrows showed up. The fixed size option didn't have a check in it (even though it was clearly at fixed size, but when i applied after changing the distance betw icons then the check showed up.
yeah, I know this doesn't help. When running DTX did you get any script warnings? Do you have an antivirus that blocks scripts, possibly set to silent mode?