I don't know if this is a bug or a feature request!
I have included a sample project.
In the resource editor only the first *.h file is recognized as id defiitions. For example: try two give the dialog the id 'ID_TWO', it will not be found. (bug?)
If one edits the rc file by text, you can do this and the ide knows, that ID_TWO is 2000.(ok!)
I have also tried to include the second include file (res1b.h). But no luck.
This is always a big barrier in modularize my projects. The only solution is, two use either one big *.h file or more than one *.rc files.