I know that Premiere Elements can not work with that file format.
I can't speak for Encore. However, there are a number of Encore (as well as Premiere Pro) users on the community forum at videomaker support site http://Muvipix.com.
They're a very friendly group, and someone usually answers questions posted there within an hour or so.
Encore can work with true Sub-Titles (and also Closed Caption, which is similar, though different), and can use most common Sub-Title text formats.
For specific Encore questions, including Sub-Titles, the Encore Forum is a great place.