2 Column group reverting to single column when conditional logic is applied

Hi.

I have set up a form with grouped areas set out into 2 columns. The group is made up of multiple dropdown boxes setup using conditional logic. When initially previewing the form all looks great. 3 drop down boxes are shown, 2 on the top line and 1 below. However when I drop down and select a different option the dropdown box (top left) the second dropdown box (top right) disappears and it’s replacement dropdown box (according to the conditional logic) appears below the top left option! I hope this all makes sense? What I’d like to happen is the 2 column layout continue no matter what option is selected.

Secondly, I’d like to add a css class style to the forms submit button. I can see it’s possible to change CSS styles, but am I able to add a CSS Class?

Many thanks