Hello @DanGarkusha!

Glad you could make it work the way you needed, and thanks for sharing the outcome!

I was looking latest CheckBox selection model documentation and nothing clearly seems to implement the behavior described this far. So I'm afraid no, actually not even the most current version of Ext.NET implements this selection approach.

But I believe with the RowModel's Multi select mode and a CheckColumn, you'd be able to implement a more complete approach to the selection rules you want, supporting elaborate ctrl and shift keys selection through the records.

Or even extending/overriding the Ext.NET 4.7.1's CheckBoxModel, you'd have the benefit of the ctrl and shift modifiers while selecting, as well as keyboard selection. All you would have to do is modify it so that checkbox selection always worked as if the ctrl key was depressed.

Hope this helps!