Major cleanups (removed things no longer used by the new backup).

Major cleanups (removed things no longer used by the new backup).
Microsoft must surely be jealous (do more with less).

Fixed a bug: if somehow the block weights in a page become discontinuous,
moving things up and down will slowly improve the situation until it's back
to normal again. It would just fail without notice before.

Fixed a bug: you could add multiple instances from a block that didn't
allow it if, after adding the first, you just hit Refresh in your browser.

Fixed a typo: missing / inside filepath