Jim:
Here is the script. When I use GrillSel in a column formula I get the error message. However, I do see the value of GrillSel in the log after a selection is made.
dt = datatable("Sales w Corrosion Updated");
GrillList = AssociativeArray(Column(dt, "Grill") << getValues) << getKeys;
SaleYrList = AssociativeArray(Column(dt, "Sales Year") << getValues) << getKeys;
ClaimYrList = AssociativeArray(Column(dt, "Global Year") << getValues) << getKeys;
PartList = AssociativeArray(Column(dt, "grill parts") << getValues) << getKeys;
Dlg = Dialog ("Select Grill",
vlist(Selection = listbox(GrillList),
button("OK")));
eval ( dlg );
GrillSel = dlg ["Selection"];
Show( GrillSel );