And the turn button doesn't return once you hit done on this screen?

Usually you get this screen when your flagship (or other survey ship) encounters a wormhole anomaly and is transported outside of it's range from your Area of Influence (AOI). This is no big deal other than you can't survey any more anomalies until you get back into range of your AOI. THis is usually a good way to meet far off AI's and minors much earlier than you otherwise could.

I've never heard of this causing the game to freeze up in any way.

So what is the nature of this "interesting development" that you mention?

If this causes any kind of game lockup usually the best thing to do is to post the contents of your debug.err file that's in the same area where your save games are stored.

If I had to guess there was probably some problem calculating your Area of Influence. That would explain why this would occur anytime *any* ship was moved. Also if the game could not calculate your Area of Influence then it could never finish calculating the path back to your AOI thus the loss of the End Turn button.

It might have been marginally interesting to load the task manager and see what percentage of processing time the galciv2.exe process was taking. I assume that it would be the bulk of the time.

Any sufficiently advanced technology is indistinguishable from magic. There are endless infinities of error conditions that have been corrected by simply pulling the power cord.