Anyway, a bad idea for OFP:
- There are no "maps". You don't create a small 3D world from scratch and place some enemys in it.
- OFP is "islands" and "missions". The normal way is to create a mission on an existing island, as creating a good island will take longer than a mission.
That's because an island is not just a "map", it's a big terrain for many possible missions.
- If your hometown doesn't look like the OFP buildings, you'll have to model and texture your own objects with another programm. (called o2) - And you'll have to model them with performance in mind, not as detailed as you would like to create them.
- If you just want to recreate the roadmap in main and don't care about the terrain and buildings, you can do it without island editing and modeling.
Just find an empty space on an island, install the Editor Update Addon and place roads and houses how you need them in the mission editor. - But it's very likely you'll encounter performance problems with a big city.
- And at last you don't want to do all this, really! ;D
Just because the OFP AI can't handle villages like you know it from other games for which you create "maps". Either they will run around and through houses (walls!) like headless chickens, or you'll place them stationary while creating the boring atmosphere of a shooting range.