Before SolidWorks 2011 borrowing a license was a little cumbersome as you had to make sure to borrow a Standard seat as well as a Professional or Premium if you wanted extra add-ins. Also the list of possible products was extremely long and had nothing to do with what licenses you purchased.
In SolidWorks 2011 there were changes made to the borrow function to clean up the user interface. It now shows only what licenses you purchased and you no longer need to select a Standard license to be able to use the software.
For example on my license manager I do not own a seat of Standard so it shows zero available but I have plenty of Premium. This is working as designed and if yours looks this way not to worry. Going forward you do not need to borrow the Standard. It will do this for you as the License Manager knows you need this.
That doesn’t mean you cannot borrow a Standard license if you want it takes a second step to do so. The process involves selecting, for example, the Premium that is available and click “Borrow”. Then the Select Product dialog comes up and this has a pull down that allows you to take either the Premium or just the Standard.
Once the product is selected I can then click OK and it will show me what I have borrowed and until when. Now at this time you need to disconnect from the server to be able to use the borrowed license. If you do not disconnect you will just take another license from the pool.