London Heathrow to Pristina via Zagreb return. Online check-in was difficult from London. It allowed me to choose my seat then the on-line process failed. On my return on-line check was not available then again it was not available for BA and Swiss who I have used on this route. For a European short haul airline the onboard service was excellent. FA's were friendly and the food good. The longer sector from LHR-ZAG return included a proper cold meal. A full and free bar service. Even on short sector ZAG-PRN included a sandwich and bar. This is welcome given the poor availability of food to purchase at PRN and ZAG. Also the tight transfer time at ZAG restricts any opportunity to purchase food/beverage. The only problem I have with Croatia Airlines is the transfer at Zagreb as the airport is a joke and the tight transfer can be stressful due to slow security processing.