I've created a presentation of about 40 slides, and started importing pictures -
large pictures, and many of them. At one point, the presentation was about 130
Mb in size, but OOo was holding out just fine. But because I want to give this
presentation on a slow laptop, I decided to resample the pictures to screen
size, instead of importing them and letting OOo resize them. So I deleted some,
resampled the originals from my hard drive, and imported them again. So far so good.

But then, OOo crashed (probably because I was using way too much memory space,
running OOo, Gimp, WinAmp5, Firefox at the same time) and when I restarted, the
images had gone. Well, okay, stuff happens, so I started importing them again. I
saved the file, closed the program, opened up again, and they had gone again. No
crash this time. I also noticed that the file had suddenly become password
protected, fortunately leaving the password blank was enough to open it.

I started adding the pictures again, to see if I could reproduce the error. By
now, I didn't even have to save to see the pictures disappear: just flipping
back to slides on which I had already imported new pictures would show that they
had gone. There is still some sort of picture placeholder, but the pictures have
really gone (I've checked inside the xml file archive). I did not just link to
the pictures, I really imported them.

I'll try adding the file to this issue, because I think that it may have become
corrupted in some way during the crash; although over at OOOForums I've read one
or two similar stories of disappearing pictures without mention of a crash.

On the plus side, this has dramatically reduced the size of my presentation,
from 130 Mb down to about 13 Kb. Only problem is, I'm expected to use this
presentation tomorrow.