Look for function getStarLevel in inc_func_member.asp and there search for the following. Add the red lines and all admins will have an additional star.
case "3"
if (fM_POSTS < cLng(intRankLevel1)) then Star_Level = ""
if (fM_POSTS >= cLng(intRankLevel1)) and (fM_POSTS < cLng(intRankLevel2)) then Star_Level = getCurrentIcon(getStarColor(strRankColorAdmin),"","")
if (fM_POSTS >= cLng(intRankLevel2)) and (fM_POSTS < cLng(intRankLevel3)) then Star_Level = getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","")
if (fM_POSTS >= cLng(intRankLevel3)) and (fM_POSTS < cLng(intRankLevel4)) then Star_Level = getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","")
if (fM_POSTS >= cLng(intRankLevel4)) and (fM_POSTS < cLng(intRankLevel5)) then Star_Level = getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","")
if (fM_POSTS >= cLng(intRankLevel5)) then Star_Level = getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","") & getCurrentIcon(getStarColor(strRankColorAdmin),"","")
'Extra star to admins
Star_Level = Star_Level & getCurrentIcon(getStarColor(strRankColorAdmin),"","")