You can add this to your nations.ini: 
  
[NationXXX] Name=NewCuba DisplayName=New Cuban Air Force Alignment=FRIENDLY PilotNameList=NamesSpanish.lst RankList=RanksUSAF.lst CallsignList=CallsignsUS.lst Formation.Fighter=USFighter Formation.Attack=USFighter Formation.Bomber=USBomber Formation.Transport=USBomber Formation.Tank=USTank Formation.MobileAD=USAD PilotTrainingStandard=Average GenderRatio=0 DebriefSuccessMusic=DebriefSuccess.wav DebriefFailMusic=DebriefFail.wav DebriefKilledMusic=DebriefKilled.wav SpeechFile=USAFSpeech.cat SpeechTextFile=USAFSpeechText.cat Medals=MedalsUSAF.ini MedalTextFile=MedalsUSAF.str ActiveDate=1964 AlternateDecal=USAF_OLD   These are the Camo Color Values (RGB) I used for the skin:  Dark blue    93,110,126 Bright blue    130,153,176 Grey        150,149,145 
  
In the Rar-File are both the proposed flag and insignia...Happy skinning. 
New Cuba.rar