Descriptive Problem Summary:
Client -> Reconnect fails to actually reconnect you on remote servers. This does not seem to be the case on local servers. This, for some reason, depends on server version, not client version.
The server name reappears and some of the verb panels do, but the map stays black and verbs don't work. It seems like you disconnect shortly after connecting but before anything really happens.
I've only tested this on one game and I very much hope it is as simple to reproduce as I've said, because if not there's no way I'll be able to find the cause in half a million lines of code or so

Numbered Steps to Reproduce Problem:
1. Connect to a server hosted not on your own computer
2. Select Client -> Reconnect from the right click menu on the title bar

Code Snippet (if applicable) to Reproduce Problem:
I really hope this doesn't require any specific code, because I will not be able to find it

Expected Results:
Reconnect successfully

Actual Results:
Don't reconnect successfully

Does the problem occur:
Every time? Or how often?
Every time I've tried it. EDIT: Actually not every time, but most of the time.
In other games?
No idea.
In other user accounts?
At least one.
On other computers?
At least one.

When does the problem NOT occur?
When you simply close and relaunch Dream Seeker, or when the server and client are running on the same computer. Or something.

Did the problem NOT occur in any earlier versions? If so, what was the last version that worked? (Visit http://www.byond.com/download/build to download old versions for testing.)
This button worked fine on the latest 512 build, but stopped working when we updated the server to 513.1522. It was probably introduced earlier than that in 513, though

Workarounds:
Don't use that button to reconnect.