Datagrid internal error

[Paul Dupuis]

A customer encountered the following execution error (below) in our app 
(built on Livecode 9.6.7, MacOS 12.5). This error is occurring in the 
scrips for the Datagrid itself, rather than our code. At the end, it is 
one of our handler, "populateMe", where line 139 is where the error starts.
Line 139 set the dgProp["columns"] of grp "rwMatrixObj_DataGrid" to 
tColumnNames

tColumnNames is a variable containing a list of text lines that are 
customer entered column names, so they could be ANYTHING (up to 255 
chars, no control characters, including DEL (127)) that a user could 
type or paste into a field, including words in any language using Unicode.

As the executionContexts data does not contain the actual values of the 
variable tColumns when the error occurs, does ANYONE have any idea what 
tColumns might contain that could produce the error(s) show below?

Technical information:
Property: value is not a number: (Line 11, column 1)
Object: can't set object property: (Line 11, column 5)
set: can't set property: (Line 11, column 1)
Handler: error in statement: LayoutControl (Line 11, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDefaultHeaderButtonBehavior"
-
repeat: error in statement: (Line 5066, column 1)
Handler: error in statement: _table.ResizeHeaders (Line 5052, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDataGridButtonBehavior"
-
Handler: error in statement: _table.ResizeColumns (Line 4967, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDataGridButtonBehavior"
-
Handler: error in statement: _table.CreateColumns (Line 4737, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDataGridButtonBehavior"
-
Handler: error in statement: _table.RegenerateColumns (Line 4538, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDataGridButtonBehavior"
-
switch: error in statement: (Line 6150, column 1)
Handler: error in statement: dgProps (Line 5553, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDataGridButtonBehavior"
-
set: can't set property: (Line 5529, column 1)
Handler: error in statement: dgProp (Line 5529, column 1)
Object ID: stack "RevDataGridLibraryBehaviorsDataGridButtonBehavior"
-
set: can't set property: (Line 139, column 1)
if-then: error in statement: (Line 139, column 1)
Handler: error in statement: populateMe (Line 138, column 1)
Object: group "Table" of card "FrequencyReport" of stack "FreqReport.rwtl"
Object ID: group id 1162 of card id 1002 of stack 
"/Applications/HyperRESEARCH 4.5.4/Components/Tools/FreqReport.rwtl"