Hi. The first thread link you posted has a dead JSGME download link. A while back I uploaded a resource pack called Modding Tools and Utilities Compilation that contains the final JSGME 2.6 version.
Here's the thread link:
http://www.subsim.com/radioroom/showthread.php?t=203831
And here's another working JSGME 2.6 download link:
http://www.gamefront.com/files/21681483/JSGME.7z
Traveller