I just updated jPortable and found that the jPortable Launcher is incompatible with this new release; this is probably due to a change in the folder structure: The old path to the binaries was \CommonFiles\Java\bin; the new one is \CommonFiles\Java\App\AppInfo\bin. Please update the jPortable Launcher. (Maybe one can make the launcher work via symbolic links so that it finds the necessary files at the right place. But I don't have enough time to experiment with this and just reverted to version 73.)
This problem has been solved: There's a revision 2 for jPortable 8 Update 77 which again uses the old folder structure so that everything works fine. That was really quick. Thanks to everyone involved.
There was a build error with the files being in the wrong place as you noticed. I'd have had the release and notes up sooner but SourceForge was down. My apologies for the issue.
Sometimes, the impossible can become possible, if you're awesome!