When I move an audio loop (green) into the arrange area it will not play the sound Why???

The green loops are actually MIDI, not audio, so you should be sure to drag them onto a software instrument track or into the blank area of the Arrange Window to automatically create a new track for it.

If you drag the green loops onto an audio track you will hear nothing because the loops have no audio.

This may be helpful: https://discussions.apple.com/thread/5183897?answerId=22539894022#22539894022

Correction: if you drag a green MIDI loop onto an audio track it will convert it to an audio loop (which you should be able to hear) as I indicated in the linked thread. So something else must be amiss.

If you drag your green loop into empty space in the Arrange Window a new software instrument track will be created for it. An EXS instrument is assigned to the loop so you should be able to hear it play. This is all straightforward, so perhaps if you provided a little more step-by-step information we can determine where the problem is.