Even with phex_3.4.2.116, opening via accessing the jar file from the resource folder opens fine on Mavericks. And this is same process as the one I worked with in previous posts.

I did your test and works fine in Mavericks OSX 10.9 but not for Snow Leopard OSX 10.6 (nothing happens.)
I suspect this is because of the limitation Apple puts on Java versions for each OSX, and the system java for OSX 10.7 & above were designed specifically for the later OSX's.

I don't have OSX 10.7 so cannot test on it. And upgraded 10.8 to 10.9 a month ago to see if I liked it or not (I don't.) But I could always set up other guest OS's for testing if necessary.

Likewise all my connection, etc. installers are app bundles so all I need to do is replace with updated contents & rename the app's date.