A curable film-forming composition is provided, comprising: (a) a polymeric polyester binder comprising a plurality of carbamate groups; (b) a curing agent reactive with the carbamate functional groups of (a); and (c) a reaction product of: (1) a hydroxyl functional polymer comprising the reaction product of: (i) a monomer comprising at least two ethylenically unsaturated double bonds; (ii) a monomer comprising a carbon atom that is bonded to four moieties wherein one of the moieties is a hydrogen atom and the remainder of the moieties comprises an alkyl group, wherein at least one of the alkyl group-containing moieties comprises an ethylenically unsaturated double bond; and (iii) at least one monomer that is polymerizable with (i) and (ii); and (2) a lactone or lactam. Also provided are a multi-component composite coating composition that includes the curable film-forming composition described above and methods for forming a composite coating on a substrate.