i went into the appearance > widgets area of wordpress and it still said i had 4 widgets.
@mattyn1990 Of course, BP Default registered 4 widget areas in the footer. You only need to use the first footer widget area since we made it one widget area only in the footer. No worries.
if i was to start all over again from BF-default file and create the child theme from scratch what files would i need to take over with me ?
To create a three-column child theme of BP Default theme with one footer widget area like you wanted, you would definitely try to avoid bringing over template files from the BP Default over to the child theme as much as possible.
Therefore, you'd start only with
a) your child theme's style.css
b) your child theme's blank functions.php
c) a new file sidebar-second.php and
d) BP Default theme's footer.php which you need to revise per your one widget-area only in footer
e) BP Default theme's sidebar-footer.php which you need to revise per your one widget-area only in footer
You can call the 2nd, 3rd and/or 4th footer widget area/s in sidebar-second.php. You'd need to override the style (width, padding, margin) for the 2/3/4th footer widget areas set by BP Default theme.
You need to create a function in functions.php file to insert sidebar-second.php file into the body of the theme. And then comes the part where you'd have to use your CSS skills to align the new sidebar.