[Plugin: Bootstrap Shortcodes] folding columns and responsive images

I’m used to using bootstrap, but can’t figure out how to get what I want using the shortcodes within visual editor.

1. Collapsing columns depending on size of viewport:
Can you add more than one class like normal bootstrap.. so that as the screen size gets smaller you can have the columns fold under each other.

Like this: class=”col-md-3 col-sm-6 col-xs-12″

Where there are 4 columns for med to large sized screens, only 2 columns for small screens, and only 1 column for tiny screens?

2. Responsive images inside the columns.
How do you add an image and have it be responsive. When I use the insert from media library, it always adds a width and height, which will kill responsiveness. I’ve tried deleting those items after inserting the image, but still can’t get the image to play nicely. If I put it in the left column of a 2 column grid, then when the screen gets smaller, the text in the 2nd column just overlaps the image.

Any help would be greatly appreciated! (Deadline to get this up online is tonight!!!)