Sub Test()
Dim CurrentUCS As AcadUCS, NewUCS As AcadUCS
Dim orig() As Double, xvec() As Double, yvec() As Double
Dim xpnt(0 To 2) As Double, ypnt(0 To 2) As Double
Set CurrentUCS = ThisDrawing.UserCoordinateSystems("123")
orig = CurrentUCS.Origin
xvec = CurrentUCS.XVector
yvec = CurrentUCS.YVector
xpnt(0) = orig(0) + xvec(0)
xpnt(1) = orig(1) + xvec(1)
xpnt(2) = orig(2) + xvec(2)
ypnt(0) = orig(0) + yvec(0)
ypnt(1) = orig(1) + yvec(1)
ypnt(2) = orig(2) + yvec(2)
Set NewUCS = ThisDrawing.UserCoordinateSystems.Add(orig, xpnt, ypnt, "New_UCS")
End Sub