Hi Pontus,
You would have to derive a custom cell type like the ones( \4.4.0.49\windows\Grid.Windows\Samples\CustomCellTypes\DropDownFormAndUserControlSample). It requires a model class and a renderer class. The model class handles the serialization requirements for the control and creates the renderer class. The renderer class handles the UI requirements of the cell. Then to use your custom cell type in a grid, you need to register this celltype with the grid as shown in this sample.s\Syncfusion\Essential Studio\4.4.0.49\windows\Grid.Windows\Samples\CustomCellTypes. Also the attached sample shows you "How to attach custom celltypes in a GroupingGrid?". It also implements the CheckedListControl as datasource. Please try the sample and let me know if this helps.
Sample :
CustomCellTypeSampleHere is a forum thread that discuss with the simillar issue.
http://www.syncfusion.com/support/Forums/message.aspx?&MessageID=11288Best regards,
Haneef