Apple Logic Pro /LogicExpress Discussion

Hi - I have been trying to create a loop of a drum pattern. Here's
what I'm doing:

1. I set up an instrument track and assign the exsp24 set to a drum
kit to the track.

2. I use the pen tool to highlight a measure

3. I open up the measure in the hyper editor and create my pattern

4. I click on add region to apple loops and the window comes up but
the radio button that says "one shot" is selected and it won't let me
change it to loop. 

What do I need to do so that it will allow me to select loop?

Thanks

David