Need information for privacy policy

I am currently having a lawyer specialised in internet law, testing my homepage for law conformity.

He informed me that if using UserEcho as a feedback system on my homepage by german law I need to include the following information about userecho into my privacy policy:

- what kind of data is collected or transferred

- under which circumstances

- to what other place or system

- and how the user can avoid that

Can you please help me answering these questions?

In fact an answer to this post might also be helpfull to every other german user who wants to include userecho rightfully into their homepage.

Thank you.