I need to do a 'component' this component uses Joomla! com_users to login and then connect a external db the use a form for sql updates.

In first time I install Joomla! and develop a custom component (not using fabrik because I cant do CroosDB JOINS) but i feel Im not doing the things the best way.

1. I only use com_users for Joomla CMS
2. I don't need any articles, modules, categories, templates, etc
3. I don't need to install other any extensions

My app only uses com_users for login and connect then in other external db updates

My questions:

**Why i should use Joomla CMS if nothing (except com_users) is useful for me?

Can I use Joomla Framework and then "copy" com_users and use it?

I'm right when I say that my best option is to develop the "component" directly on Joomla Framework?**

I already install Joomla Framework (an hour ago) but i can't find enough documentation

Hope this question is for this section

BR