Fixed gh #520. It turned out that on creation AM2DSummingABEditor simply set the analyzed data source input to the 0th item in the names combo box. I've added a check against already having a data source selected and finding that one by iterating through the list. Also made a minor change to try to help with the PGT drop points ... I don't think it's really helped. Also removed some commented out code.
Merge branch 'master' of github.com-acquaman:acquaman/acquaman