Moved from the Creative Cloud to the Premiere Pro forum. They will be able to help you here.
I would honestly talk to the makers of Articulate. Find out why their software isn't working with files it claims to work with.
There software does work with FLV - just not the codec that we're restricted to in Premier..., as the AVS software allow 4 codecs that all work! In the past Premier allowed us to choose the version of FLV it was compatable with but no longer - why?!? Are there a set of pling ins missing/deleted from CS6?
The Articulate forum has been much more help than this one. Blaming the other company is unhelpful when it's able to take in FLV's as can be seen by it taking the AVS FLV's
Adobe did drop support for Sorensen Spark. If you need that codec, you'll have to use other encoders.