Audirvana Plus not working can't load license file

I bought audirvana plus after trial version expired. received downloads and transfered into applications.I click on load license file and I am sent into appl. but can't go any further I see AP in the list but it is not highlighted so cannot select. help
I had exactly the same problem when I first started using Audirvana Plus. Here is the link to my post on Audiogon concerning this problem; and more importantly, the fix!
problem solved thanks. Another issue, I use my ipod with remote app. to control my mac mini. The volume control on the ipod is barely open to get sufficient gain. I reduced the preferences vol. to compensate now when I increase volume on ipod, setting won't hold, it goes to lowest setting (no audio). If I increase pref. vol. to max gain, the ipod works fine ??
Look at preferences for Audivrana. You may have iTunes volume disabled