float Montage_PlayInternal ( [UAnimMontage](API\Runtime\Engine\Animation\UAnimMontage) * MontageToPlay, const [FMontageBlendSettings](API\Runtime\Engine\Animation\FMontageBlendSettings) & BlendInSettings, float InPlayRate, EMontagePlayReturnType ReturnValueType, float InTimeToStartMontageAt, bool bStopAllMontages )