Crashed MDS Add-In for Excel - Need to enable it annually

I have SQL Server 2012 Master Data Add-In for Excel 2010 (32bit) installed. Everything works OK until I define the domain-based attribute. It runs forever....Updating attributes takes hours...keep running... So I have to manually shut down Excel. Then when I open Excel again. The Master Data add-in is not in the menu anymore! It is disabled by Excel to protect the program. To bring it back, you have to manully enable it. See below.