That you should try before spending money by calling CSS 
Keith Abluton does a great job and putting together a collection of activities you should carry out before you call CSS.
Check out his blog post at http://blogs.technet.com/b/keithab/archive/2012/02/15/top-troubleshooting-tips-to-try-before-calling-support-for-isa-tmg.aspx
for all the juicy details.
HTH,
Deb
DEBRA LITTLEJOHN SHINDER
MVP (Enterprise Security)
“MS SECURITY”
[email protected]