Great blog for setting up Lync 2013 with UAG

Great Blog from Georg Thomas on the subject.
http://www.ucfoc.us/2012/10/publishing-lync-server-with-forefront.html
For me I had pointed the lyncdiscover service to the edge instead of the lync front end.
When I followed his post everything worked for me.
I also used a (not supported) wildcard certificate on the HTTPS trunk and so far no issues are detected with this.

An alternative is to use IIS ARR:
http://masteringlync.com/2013/02/12/using-iis-application-request-routing-arr-as-a-tmg-replacement/