JOOMLA Help! User admin, registered content

Desperately need your help with our joomla site. Basically we have resources (white papers, checklists, etc.) that only registered users can access/download OR visitors that fill out a form.
We need:
- A form that allows them to either register (create a password) or just fill out the form (no need of a password)
- Send user info to Salesforce when a new user registers or fills out a form.
- Track using a data field with the resource they were on when they registered or filled out the form (in other words, track which resource motivated them to register). Could be a hidden field in the form.
- Upload a CSV file with our current clients with a username & password so that they don´t have to register.
- Integrate with our marketing email platform (currently looking for one btw- any suggestions greatly appreciated!) assigning users to the correct mailing list per their selection in the form. (not as necesary if we can download manually and filter through a data field)

Any method/plugin/extensions you could recommend? Would it be best to find an advanced form plugin or a catalog type of extension? If so, which ones?

THANK YOU SOOO MUCH FOR ANY HELP YOU CAN PROVIDE