display suite modifications I am using Display Suite for the first time and experimenting with the 2-columns layout.

What I didn't expect is that the module will override my existing node layout.

Can anyone tell me if I can use my 2-column layout in combination with my existing layout? This is especially important as I have information which needs to be displays outside of columns above and below it.

Thanks
i will advice you to use "Fluid two column stacked" layout. This layout provides a header region, then two left and right columns and one footer region. 
So you can display your data by putting appropriate fields in the right regions. Also if you don't have any fields in any region that region will simply not display and if you don't have data in the left column then the right column will shift to the left side.
Hope this solves your problem.