In the editor under the units tab. On the lower left there are multiple things a unit can do. Hold down the control key while selecting Lethal bombard or whatever ability you want to add. Holding down the control key allows you to select multiple abilities at one time, otherwise selecting that will unselect the other abilities. Above that list of abilities is bombard Strength and Range which you can change. Max Range is 8, but in the abilities section there is a 'unlimited bombard range', but I can't seem to get it to work properly.
I think all changes affect Future games, not games in progress. You would need a saved game editor for that, and using a saved game editor can be confusing, so I don't recommend it unless you have alot patience to figure it out. (make backups of your saves in case the saved game editor screws up the save!). Saved Game editors can be found in the utilities forum. There aren't very many available that has been updated to v1.29f.
