DD2 told me that she wrote on her VR question sheet at the 11+ at CoCHS on 22 September this year. As far as I can tell, it didn't prejudice her marks and she scored a very respectable 360 (standardised) with a 73/80 raw score. She isn't home at the moment, so I can't say whether spare paper was issued on the day - I'll check when she gets back, although I'll probably get the standard "I can't remember" response
She pretty much erased all memory of the exams the minute she stepped out of the hall that day and we'd made a pact not to talk about it, anyway. One thing she does remember, is that the girl sat behind her, constantly Jangled little bells for the first 10 minutes of all three papers - she even remembers the girl's name
When I telephoned CSSE, they said there wouldn't be any spare paper - but I'd highly recommend calling and asking, as I know from experience, that you don't always get the same answer twice, when it comes to CSSE
Update: She was given scrap paper in the VR but not the other papers.