my dog had an ulcer on her eye just after xmas. it has healed well but there is a noticeable scar. She is not one of the high profile breeds where I presume she would fail a vet check. But will she be penalised for it? and do I need to get permission from the KC? If it makes a difference the ulcer was caused by an injury and the breed is not particularly prone to eye problems

Ask your vet to give you a letter explaining that the scare was caused by a trauma, make a copy and take it with you, should not make much of a difference as eye problems are not one the breed suffers with.

However, judges being human they will, given a choice of two dogs of near identical merit, probably go with the dog with clear eyes.