Actually looks like the move was triggered correctly but happened only after 15 minutes, so the success wasn't reported by the standard move form, so I assumed that it wasn't going to happen and made things worse by reverting the translatable page move too soon, when Translate wasn't aware of the new location of the translation pages, which are now left orphan......
https://meta.wikimedia.org/w/index.php?title=Special:Contributions/FuzzyBot&dir=prev&offset=20121109130403&limit=100&target=FuzzyBot

You should not be able to access the normal move page form for tranlatable pages, nor should you be able to do any actions on them before the move is completed.

(In reply to comment #2)

You should not be able to access the normal move page form for tranlatable
pages, nor should you be able to do any actions on them before the move is
completed.

So comment 0 is correct in saying it should have ignored the translatable page?

(In reply to comment #3)

So comment 0 is correct in saying it should have ignored the translatable
page?

Niklas: Could you answer Nemo's question please?
Any ideas about the priority to set here?

(In reply to comment #4)

Niklas: Could you answer Nemo's question please?
Any ideas about the priority to set here?

Probably this bug is invalid and I was just confused by bug 44865. I'll test both later today, as Meta is now at 1.22wmf1.