Sometimes when I start my computer the rainlendar icon appears on the wrong side of the screen (left instread of right) in ubuntu 12.04LTS.
This happend with version 2.10, with the latest beta I didn't experience it yet, but I can't confirm its fixed.
I couldn't see a topic with "known bugs" or something simular so I thought I would mention it.
An other thing, the icon displaying the date doesn't align properly with the rest of the icons in the task bar.
If you check the space between the native system icons and the Rainlendar icon you notice the difference. Or compare both screenshots, one is with Rainlendar and one without.