You may have already tried clicking on the Skylendar entry and had nothing happen.
Don't Panic.
It's because Skylendar uses a postgresql database to store its data.
In order to use that database your user needs to be given access to it.
Click on the Skydmin entry.
It will ask for your root password since it needs admin privileges.
Click on the Install/Upgrade button and click OK on the popup that asks if you want to install the database skylendar.
When you see Installation Finished ! come up, click on the Accesses tab at the top.
Scroll down to find your username. Click on the false next to your username and press the t key to change it to true.
You can create a password for the database if you like, or leave it blank.
If you create a password you will need to enter it each time you start Skylendar.
Click OK
The database setup program will exit and you will now be able to run Skylendar.