How are you doing with disk space? Did this come up the first time you launched the game after a crash? Does it happen continuously or was it a one-off?
Disk space is quite enough, there was no crash the session this happened, and it happened the first time and, as far as I know, just this once yet.
But as I am testing the "Oolite Extended" meta-oxp, I was wondering if it pointed to some as-of-yet unknown problem in there. The oxp has nearly 900MB ...
My inclination is to assume that this is a bug in GNUstep’s binary property list code, although it could also have happened as a result of a crash while writing the cache.
... a bug in GNUstep’s binary property list code ...
That would imply that it is not a buggy plist or script somewhere in the oxp?
[ai.load.failed.unknownAI]: Can't switch AI for <ShipEntity 0x18bd8818>{"Docking Slit (horizontal)"} from <no AI>:(nil) to " nullAI.plist" - could not load file.
And, while we're at it, what's that? (I mean, I can see that an AI is not there, but what for does a Docking Slit need an AI? )
The Debug oxp is unrelated to that. Try a search for "Docking Slit (horizontal)" in your AddOns folder and you might be able to find the location of this one.
Two things, the bad data error message is basically saying that a particular subset of data is actually longer than it should be, and it normally happens when a file (apparently the cache file - in this case) is somehow corrupted. It can't read some data, but whether the data itself is buggy or not is another question altogether.
--
Reading the error message it looks like someone somewhere specifically defined a docking slit ai as " nullAI.plist" nothing too horrible in and of itself, I suppose, but the error message is because oolite cannot find the specified file. Why? Because of a typo. According to the error message it's looking for a file with a name starting with a space: " nullAI.plist" is different to "nullAI.plist". Do look for that specific string (the one that starts with a space), fix the typo, and suddenly you won't have that error anymore. As if by magic.