> Doesn't handle a taskkill (os reboot) but I don't
> remember if 3.33 did.

No, this is something which was never implemented.

This one is much harder to handle. The best way is generally to manually
remove new.* files, and rename old.* files to "new.*" versions, but you'll
lose killed session data.

One possible solution would be to merge the two caches together, but the
half-built state would probably cause some troubles anyway.