Install creators (like Wise) can do patches from previous versions that (in theory anyway) only include the bits that have changed. So you might be able to use something like that to do what you want.
benoit wrote:
That is my wish but now i have a question : when i use "create executable and data file for Each File", how is it possible actually to find the ilm file that correspond to my different page in the cd-rom (000000a.ilm, 000000b.ilm, 0000001.ilm.... : how does the program work to numbered the file)
I think they're just numbered in the order of the pages in the publication.