Actualy, all of the town is being detailed. Each sector is about four blocks in extent, mapped by block, so all you need to do is skip the module that covers an area where you have developed things--or use those parts of it where you have not detailed anything for your campaign. These modules are by no means mandatory, so all can be ignored. OTOH, they do all the drudgery work for the Castle Keeper, include adventure scvenarios, and a slug of adventure hooks for the CK to use.
I plan to use the lot, alter some entries to suit my own ideas and the needs of my group.
Cheers,
Gary