Well the old stuff still works with the old stuff and there are tools in DS that helps old stuff fit the new stuff but since when has game development ever been problem free. If it was that easy one could buy “Developer in a box” at S-mart. 
As for exporting static mesh exports just fine and skeletal meshes import fine into 3ds Max and Motion Builder (along with a few other apps) so the problem is not with Daz3D’s FBX exporter but with Unreal 4’s importer so if one really wants to do a direct DazStudio > Unreal 4 then Epic has to fix it on their end. It would be nice if Epic did jump on the Daz Studio bandwagon as I’m also interested in doing some animated shorts and not just use UE4 to make a game.
P.S. I still use PhotoShop 5.5 because it does the job that I need it to do in hand.