Set cell type for dhtmlxGrid subgrid data

I’m using subgrid functionality with dhtmlxConnector (.NET) and I would like to add a cell type attribute to the certain rows that have subgrid data. How is this possible

Currently cells all have the value and I want to manually set it for for those cells with sub grid data. Currently it will just display the URL of the data instead of loading the URL and populating the subgrid

It seems I managed to solve it as I was using the wrong column type thus the is no longer needed

Incorrect code: config.SetColTypes(“sub_row,ro,ro,ro,ro,ro”);
Working code: config.SetColTypes(“sub_row_grid,ro,ro,ro,ro,ro”);