Also keep in mind that the choices you make with cover terrain will affect the tactical decisions made during the battle. For instance the addition of a wheat field or tall grass may provide concealment for advancing troops in a large open area. Likewise the addition of a stone building or trees in the right location can help provide cover terrain for defending units making them harder to hit. One of the golden rules to remember is to save often. You will find its better to be cautious than it is to have hours of work go up in smoke.
Editors can crash and the electrical service can have random power dropouts.
It only takes one time losing hours of work to learn this lesson, a voice of experience talking here. The next step is to define the victory locations. You will need to decide from your readings what was the intent of the battle. Was the capture of a specific cross road, hill top, or town the reason for the engagement. After answering this question you can then set the appropriate hexes as the victory point hexes.