You can add lines to help troubleshoot. For example to see if the ingroup function is failing (probably), or the Use command is failing.

 Code:
If InGroup( "A.ABCG" )
	"Is In Group A.ABCG" ?
	USE G: "\\share\ABCG"
        "Use G: Results: "+@SError ?
Else
	"Is NOT In Group A.ABCG" ?
EndIf
If InGroup( "A.ABCL" )
	"Is In Group A.ABCL" ?
	USE L: "\\share\ANCL"
        "Use L: Results: "+@SError ?
Else
	"Is NOT In Group A.ABCL" ?
EndIf

;**** Temporary Drive
	USE T: "\\Share\temporary"
        "Use T: Results: "+@SError ?