I've been running into what appears to be a bug with the SecureRaidHeader ever since 2.0. In SecureRaidGroupHeader_Update, it calls GetRaidRosterInfo() for raid indexes 1 to GetNumRaidMembers() which is normally just fine. However, sometimes GetRaidRosterInfo() is returning nil (for at least the unit's name) and triggering an error message:

Date: 2007-01-15 05:01:04
ID: 51
Error occured in: Global
Count: 1
Message: ..\FrameXML\SecureTemplates.lua line 884:
table index is nil
Debug:
[C]: ?
..\FrameXML\SecureTemplates.lua:884: SecureRaidGroupHeader_Update()
[string "GridLayoutHeader1:OnShow"]:2:
[string "GridLayoutHeader1:OnShow"]:1
[C]: Show()
Grid\GridLayout.lua:760: LoadLayout()
Grid\GridLayout.lua:698: ReloadLayout()
Grid\GridLayout.lua:551:
Grid\GridLayout.lua:545

Line 884 is: sortingTable[name] = "raid"..i;
name is the nil value mentioned in the error message. name comes from GetRaidRosterInfo(i) on line 877. i comes from 1, GetNumRaidMembers() on line 876.

A simple check to see if name is not nil in the if that begins on line 878 would seem to be all that is necessary to avoid the error.

876|		for i = 1, GetNumRaidMembers(), 1 do
877|			local name, _, subgroup, _, _, className = GetRaidRosterInfo(i);
878|			if ( ((not strictFiltering) and 
879|			      (tokenTable[subgroup] or tokenTable[className]) -- non-strict filtering
880|			     ) or 
881|			      (tokenTable[subgroup] and tokenTable[className]) -- strict filtering
882|			) then
883|				tinsert(sortingTable, name);
884|				sortingTable[name] = "raid"..i;
885|				if ( groupBy == "GROUP" ) then
886|					groupingTable[name] = subgroup;
887|				
888|				elseif ( groupBy == "CLASS" ) then
889|					groupingTable[name] = className;
890|				
891|				end
892|			end
893|		end

The check for nil name has been added for 2.1.0 release, thanks!

That's not a bad idea... I'm not sure if it'll make 2.1.0 though.