Is there a way to change the column width of elements (especially relevant for responsive design)?

Yes, all ACRIS elements supplied with this plugin allow you to define the column width, column order and column spacing. These settings can be found under the block settings of the respective element. Here you can configure the column width differently for various devices (tablet, mobile, desktop) on the basis of a grid of 12 columns (e.g. for the desktop display the first column should take up 25% and the second 75% of the screen and for the tablet both columns should be 50%).