How to edit bbPress template files – WordPress + BuddyPress + bbPress?

I am using BuddyPress 1.6.1, bbPress 2.1.2 and WordPress 3.4.2

I follow the guide here.

In the end, I did the trick pointed out by Sarah Gooding because mywebsite.com/forums was blank right after the above installation

• Created a page called “Forums” with permalink mywebsite.com/forums
• Insert bbPress shortcode [bbp-forum-index] into “Forums” page

My questions are

1) How do I customise page templates for the forum e.g. Forum page, topic page etc.

My current theme is a child theme of twentyeleven and it has the following structure

themes/bp-twentyeleven/

/activity/

/blogs/

/forums/

    index.php

    forums-loop.php

/groups/

/members/

/registration/

header.php

sidebar.php

style.css

Notes

• Apparently, bp-twentyevelen/forums/index.php is being ignored.
• The reason for this set up is that I need the site to looks like TwentyEleven and has BuddyPress’ functionality at the same time

2) How do I make sure that bbPress functions will work for my site e.g. do I copy and past all the functions in functions.php of bbPress’ default theme over my theme’s functions.php?

3) How do I ensure that whatever I will get from 1) and 2) (probably from bbPress experts somewhere) will not conflict with BuddyPress’ functionality or my theme?

BuddyPress setting screenshots are here and here.
bbPress settings screenshot is here.