Thats easy. Use this:
http://www.filefront.com/14686583/Destr ... el_V01.exe
Just throw it in your games mainfolder. Before starting the game, start the prog. Type in the desired destrucion level (just a number between 2...100). To reset (Destruction level "0") start prog again and type in "1" ("1". Not "0").
Example, Le Havre, 20 or 30 % destruction level (Don't remember exactly):
No bombs nor destruction brush is used here. It's the original map and it works with everey map.
Well, the prog is quite simple and just sets all types of buildings (types, not single buildings) randomly depending of the desired destruction level to "destroyed". So the results will differ from map to map depending of which buildings the map uses. Nevertheless the results are quite good. Mostly groups of the same types of buildings are set togther in a map, so there will be some kind of bombed areas clustering.
Of course it is possible to set different levels to different types of buildings (not with this version of the prog), may be i'll program this later. Even setting different percentage for each building would be possible, but that would be not so easy and quite diffcult to administrate, so i think this would not be worth the costs.