Classifieds contact seller e-mail

Hi there,

I have three questions regarding the contact seller button/ option within the classifieds plugin.

1.) This is the message a user gets when someone contacted him/her:

Hi admin, you have received message from:

Name: webmaster
Email: info@xxx.nl
Subject: Interesse
Message:
Interested in classified X

Classifieds link: http://www.fashionswaps.nl/classified/b-loved-winter-muts/

Where and how can I customize/ or at least translate this message?

2.) I'd also like to know why the message is not shown within the messages/ notification option of Buddypress? Now the whole messaging goes behind the website. Is there a option to also get a notification within Buddypress? For example by using the "messaging" plugin?

3.) I would also like to hide the "contact seller" button for not logged in members. How can I do this? Hardcoding is an option for me. Even though I prefer another option. But please let me know what I can change where.

And then a little question. In the video of the classifieds plugin you see some sort of search filter on the right (widget area). Is this a feature of the plugin since I can't find it. Now I'm using a non WPMU plugin to achieve something similar.

Thank you for your help and time!

Kindest regards,
Steven