Polycom VVX 500 and SLA

I have the latest version of AsteriskNow with FreePBX installed. I’d love to tell you what version of each is but I don’t know how to find that.

I would like to be able to put an active call on hold on one phone and move to another phone and pick that active call up on that phone. This is apparently called Shared Line Appearance. How do I get it to work on Asterisk? I am not very familiar with asterisk CLI and Linux but I am willing to try to make it go if given proper instructions.