Some questions for installation

Hi

It is very nice project, but I have several questions for it.

1) I already uses Cloudflare workers script under maplat.jp domain.
Are there any concern for existing scripts are overwritten by this code's installation?
2) What domain/url is this code used?
Is it possible to run it under subdomain? (E.g. my domain is maplat.jp but I want to run this on s.maplat.jp)
3) Is it possible to install this manually?
4) Is it possible to customize this code to work with other identity sources? (Like Google, Twitter...)

Regards,
Kohei