i did add may map to DefaultGame.ini too
GameSpecificMapCycles=(GameClassName="Rx_Game",Maps=("CNC-Field","CNC-Walls_Flying","CNC-GoldRush","CNC-Whiteout","CNC-Islands","CNC-LakeSide","CNC-Mesa_ii","CNC-Volcano","CNC-Xmountain", "CNC-Canyon", "CNC-Complex", "CNC-UnderRedux", "CNC-Beach_head"))
but i doubt that would make a difference
also in the same ini "DefaultGame.ini"
[CNC-Beach_head Rx_UIDataProvider_MapInfo]
MapName=CNC-Beach_head
FriendlyName=Beach_head
;PreviewImageMarkup=RenXFrontEnd.MapImage.___map-pic-cnc-walls
Size=Medium
Style=Symmetrical
NumPlayers=8
AirVehicles=Enabled
TechBuildings=0
BaseDefences=None
MineLimit=30
VehicleLimit=7
i changed nothing else
you may have delete the udkgame.ini and udkrenegadex.ini for them to re generate