Two questions there Hannah!

1, As above you have mark room to make a rounding and that includes getting to close hauled.

2, If the boat below can sail closer, you're stuffed and need to tack away! 

Once the boat entitled to mark-room is at the mark, 'seamanlike' is no longer relevant:  the boat is entitled to 'mark-room to sail her proper course at the mark'.

Mark-room to sail a proper course at a leeward mark includes room to harden on at the optimum rate of turn and rate of in-sheeting, that is, you're not obliged to slam the  boat up to close hauled or above, but if you muff your harden-on, drop the sheet or whatever, then you're taking more room than you're entitled to and your exoneration under rule 18.5 switches off.

BUT, once you are 'one or two lengths from the mark (having gone round)', you are no longer 'at the mark', and you have had all the room you were entitled to.  An outside leeward boat has every right to push you up at least to their proper course, and if they do not have a rule 17 proper course obligation (which may have been established before the mark), they can push you up as high as they like.  They are bound by rule 16 to give you room to keep clear.  If they are clear astern, then they are bound to keep clear under rule 12.

To get an understanding of how mark-room applies, look at the 'round-about' analogy in Dick Rose's paper here

http://www.yachting.org.au/site/yachting/ayf/downloads/Technical/RaceManagement/Comparison%20of%20Old%20and%20New%20Section%20C%20Rules.pdf?MenuID=Racing%5FRules%2F21002%2F0%2F - http://www.yachting.org.au/site/yachting/ayf/downloads/Techn ical/RaceManagement/Comparison%20of%20Old%20and%20New%20Sect ion%20C%20Rules.pdf?MenuID=Racing%5FRules%2F21002%2F0%2F

I don't think this is the right way to say it.

The language of the new rules and cases no longer refers to a rounding being 'complete'.

A boat entering the zone with mark-room remains entitled to it while ever she is in the zone (unless she switches it off by passing head to wind).

But if she is not 'sailing to the mark' or 'at the mark', for example, is past the mark, her mark-room entitlement has no 'content', we might say mark-room = zero.  Her entitlement does not switch off, and may again become meaningful if, for example, in light/tidal conditions she drifts back to the mark.

Whether one or both boats are sailing their proper or best courses after they have passed the mark has no bearing on mark-room.

As long as the inside boat is at the mark.  If past the mark rules 11 and 16 will apply.

Not rear-ending the inside boat is a simple rule 12.

Rule 18.5 only gives exoneration from Section A right of way rules and, at the mark from rules 15 and 16, giving room rules.  Rule 18.5 does NOT exonerate a boat entitled to mark-room from breaking rule 31 Touching a Mark.  Any exoneration from rule 31 has to be given under rule 64.1(c).

Hang on 1 moment guys she says the other boat sailed in to her transom.....surely that means she must have been clear ahead at some point and as she was inside boat how could she be in the wrong....

Were I on the PC I would find it hard to DSQ the boat that was clear ahead when the other boat came from behind and hit the transom.

Don't have a rule book to hand (or the time to look it up on the ISAF site) but as long as Hannah was sailing within the rules (and from her description she was IMO) then the other boat must be at fault.

That counts for little. What matters is whether you were clear ahead or inside overlapped when the first boat reached the zone (rule 18.2(b)).  If so subsequent breaking and making of overlaps don't count, unless you tack (rule 18.2(c)).

Context is everything Grasshopper.  Would you describe yourself as 'little idiots'?

Why?  The real utility of a hail at a mark is to establish in both boat's minds whether or not there is an overlap at the zone, on the assumption that you both know what to do once that is established.  You need to make the hail (Overlap, No Overlap) just before the zone.  Hailing once inside the zone doesn't do anything much except increase the noise-level.

Indeed it makes no difference whether you are clear ahead or inside overlapped, or whether you hail or not:  you are still entitled to mark-room.

No, once you are past the mark by as much as 1 or more lengths, you no longer need room to sail your proper course at mark, and you lose your exoneration:  if you don't keep clear of a leeward boat you break rule 11.  If a boat clear astern hits you, they break rule 12.

Why would you expect another boat to disclose their tactical intentions to you?

'Opportunity' was deleted from the rules long ago to remove the implication that a leeward boat had to hail.  Leeward's obligation is, if changing course, to give you room to keep clear (rule 16)  nothing more.  On the other hand Astern's obligation whether changing course or not is to keep clear of you (rule 12).

If it's clear ahead/clear astern rape, then you probably can't do anything about it, but if the other boat is coming up with a leeward overlap, the protest committee is going to want to hear from you that you did something  to meet your rule 14 obligation to avoid contact:  either you changed course to windward to maintain separation, or when contact seemed likely, you bore away hard to minimise impact. Rule 14 says you can't just sit there and watch it happen.

Seems a clear rule 12 infringement by the other boat to me!