I just recently upgraded to 1.0.3, and the routes.rb file in my config/routes folder seems to ignore all my custom routes.
1.0.3
MY routes.rb
I encountered the same error and found this solution, which solved it by prefixing main_app, before each of my_paths/_urls. In my case, these were links used in one of the /override.rb files.
main_app
my_paths/_urls
/override.rb
So, try: main_app.about_us_path.
main_app.about_us_path