Yep, sterling work. Its now exporting animation length based on the "Start:" and "End:" positions.
There is a caveat using this approach though; you can't do a multi-export. Because the start/end data determines the length of an animation it would mean all anims being exported using the same values irrespective of actual (needed) length. The only way around that would be to add some sort of option field per animation where users set the start and end point of each action, a bit impractical doing that though (not too mention over-complicating the script).