The 'Default Value' of my box is currently:
=Format(DatePart("m",Date(),"00")) & Right(Format(DatePart("yyyy",Date(),"00")),2) & Format(Right(Nz(DMax("[rmanumber]","maindata")+1,1),2),"000")
This works, but chops the first 0 off the number (as I mentioned before). If I change the last part as...