It's easy to add a custom column to a bin, but how do you make those same custom columns work accross the entire project so I don't have to create the columns evey single time I create a bin?

OOOh I just figured it out!!!

After you make the changes, go to the upper right hand corner where it says "Untitled", click on that and "save as" whatever you want to call it.  Then go to the top left set of menu tabs   Windows>Bin Settings>User>Bin> then set the default bin view to whatever you named that.

Shazam.

Bin view is saved when it gets closed, so if you want to see your layout in old bins, open them up and then go to that spot that previously said "untitled" and select the view you created.   Next time you log in, it should open up correctly.

There is also a bin setting (set default bin view) that allows you to apply that named saved bin view to any new bins created.

Note bins that have already been created and opened will still retain the bin view they had at that time. The setting only applys that bin view to new bins.

You can also copy that bin view to the site settings and any new user settings will inherit that bin view.

SWEEEEET!  thanks!