onRowSelect then nothing

Hello
I have a grid that is created, parsed and takes the first onRowSelect() perfectly. However if I click in that selected line I get first below. It is if the line/grid no longer exists. If I click on an coro I get second below. Of course I use this in a multitude of places w/o/e. Any ideas please?

Timestamp: 5/11/2015 12:02:29 PM
Error: TypeError: a is undefined
Source File: localhost:8083/10sdaanyd/pages/j … mlxgrid.js
Line: 171

Timestamp: 5/11/2015 12:04:09 PM
Error: TypeError: a is undefined
Source File: localhost:8083/10sdaanyd/pages/j … mlxgrid.js
Line: 171
Timestamp: 5/11/2015 12:04:14 PM
Error: TypeError: this.list is undefined
Source File: localhost:8083/10sdaanyd/pages/j … ridcell.js
Line: 41

Could you please, provide with a sample of your code with the init of your grid.

Mea culpa, mea maxia culpa
I was access a grid cell that was indeed not defined. Thank you for your tolerance for the impatient.