in xamDatagrid how to apply customize selection of cell depends on the value or background of cell.

My requirement is-

1) On launch of page the first cell of the grid to be selected. row should not be highlighted only cell.

2) if user pressing ctrl + left ,right, up or down arrow key, then current cell + next cell should be selected if the current cell is not empty and background color of next cell is gray. (by default all cells are gray except some are orange)

3) if current cell having value with background gray and trying to select next cell using ctrl + -> next cell should be selected if the next cell having a value and background gray.

4) if i am moving from one cell to another next 4 cells having value with orange background, all 4 cells need to be selected, it should not show as merged but selection should be one.

please provide some custom selection operation hints on this.