New to AREDN

Bought a Ubiquti Nanostation M5 ​airMAX US at the recommendation of a fellow ham. He is out of contact for the time being. 

I am attempting to load up the AREDN software. Can't determine which version to load. Don't want to brick my Nanostation. When I scroll down to the M5 there is a XM and XW listed as variants. And the difference is??

Thank you,

Mark Dallner
AC9DE