The updateCells function is what assigns each node to a cell depending on its location, which means setting its row and column. If you want to support nodes outside of the table, you probably want to add a TwoWay Binding on the Node.location, so that the location can be saved in the model.
And you’ll need to make sure such nodes are not laid out by TableCellLayout to be in cell (0,0) or whatever. You can do that either by binding Node.isLayoutPositioned to true if it should be in the table or false if not, or by changing the TableCellLayout implementation to skip nodes in cell (0, 0).
I cannot do your programming for you. In an earlier post, above, I described what you could do to implement that functionality, and you can see other samples for how they implement that. If you want to create and maintain a good app, you’ll need to learn how to do these kinds of straight-forward customizations.
I do not ask you to write the program for me… I just ask if you can send me example if you have one (as CellTableLayout - I can’t find it on google by the way)