@pickyaxe: On which KOReader version was that? (I had a vague memory of someone fixing the "oh noes!, last file read is gone" thing a long while back, so I'm intrigued by the crash on startup. I'm guessing the actual root cause was that bits of KOReader *itself* were deleted (specifically, UI icons), because it lives in a hidden folder. And, that, indeed, will cause a crash on startup
).
In any case, as @davidfor said, that was indeed the expected behavior
.