Custom Domains

I want to use a custom domain to host a web application from my the backendless files section. If I add a custom domain, do all the files urls that use the backendless domain become useless? Right now we have stored many images using the backendless domain to our files section and those images are tied to cells in tables in backendless. If we add a custom domain will those links still connect to those same images? I read something about the custom domain working only for the web folder in the files section, is that true? Do we have to put everything into the web folder?

If you add a custom domain, all the URLs you had prior to that will still work.

Regards,
Mark