There won't be another test server.
The reason *for* the test server was because twgs was very buggy at that time (though i did enjoy ghost ships) and new versions were coming out rather rapidly.
Since then, JP has said that the twgs will remain as it is, with no changes, unless there is a major bug found (which i doubt there will be) and even then, i doubt there would be another test server.
At the time there were *many* bugs that needed to get tested, because going from version to version, while some bugs were fixed, others were created.
Twgs as is, has been quite stable for 2 or 3 years.
Also, Rick has long since gone awol
If you are just looking for a server to "test" things, I know there are a few sysops who used to have games open purely for script testing/etc and i'm sure if you asked nicely someone would open up a game for you to do as you wish and test to your hearts desire.
If you can't find one and you *really* wanna test things, i would be willing to open up my twgs completely and solely for your own personal testing grounds.