The code that indicates the "ThisLink" should be the only prim with this code:
integer ThisLink = llGetLinkNumber();
llMessageLinked(ThisLink + 1, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 0]), ""

;
llMessageLinked(ThisLink + 2, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 6]), ""

;
llMessageLinked(ThisLink + 3, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 12]), ""

;
This prim will actually not be the xytext prims but another prim linked right before the xytext prims. So if you have like a scoreboard that was prim0 then you would want prim1 to be xyprim1 prim2 to be xyprim2 and prim3 to be xyprim3 then this will work. The trick to the xyText (especially if you are doing multiple text lines) is to know what link order each prim is in relation to each other.
Furthermore if you wanted to have multiple lines you would have to modify the base prim to change the names for that line so line 1 would be the before mentioned code and then line 2 would be
llMessageLinked(ThisLink + 4, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 0]), ""

;
llMessageLinked(ThisLink + 5, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 6]), ""

;
llMessageLinked(ThisLink + 6, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 12]), ""

;
Line 3:
llMessageLinked(ThisLink + 7, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 0]), ""

;
llMessageLinked(ThisLink + 8, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 6]), ""

;
llMessageLinked(ThisLink + 9, SET_CELL_INFO, llList2CSV([SET_LINE_CHANNEL, 12]), ""

;
and so on...
Hope this helps
-cor-