A childminder that I know did and it cost her a fortune for the inital outlay - to get the ball rolling. All the NCMA did was to give her advice on how to do it, She had to pursue the correct channels - small claims court etc and even then she found it hard going. She was awarded the amount but because the parents said they could only pay £1.00 per week that was what it was set out.
I know that she considers the "contracts" not worth the paper they are printed on now and according to her the NCMA where not of any help or use at all.

This is only one minders opinion though. She sticks to her guns - no payment when specified (ie at the end of the weeks session) no more service till paid up in full. I think she also now requests advance fees.

Thank fully I have not had this problem - just others where the parents think I am a glorified sitting service