On the FreeStack R iFrame stack, the width is set by default at 100%, i.e. the iFrame itself will span the width of the container div it is within and/or the width of the screen on the device the site page is being viewed on.
The FreeStack R iFrame height is set using the stack’s iFrame Height hud control.
The FreeStack R iFrame’s scrollbars can be set to be hidden or displayed using the stacks Set Scrollbars Display hud control options.
Keep in mind that the iFrame’s responsive display styling is for the iFrame itself. No iFrame can make any remote page content be responsive that’s called and displayed within it, if it’s not styled that way to begin with. The remote page content’s responsive display styling is controlled by whatever css styling is set for that page in the remote page’s css style sheet(s). If the remote page is NOT styled to display in a responsive manner then only a portion of the page will be displayed when viewed on mobile device screens smaller than the width of the remote page content. If the remote page is styled to display in a responsive manner than that remote page’s content should scale down and reposition its page elements to fit within the iFrame area.
My suggestion is to view the original catalog web site page on a mobile device to see how it displays to determine if it is styled to be responsive or not. if it’s not, then you need to set the scrollbars to show so they can be used on mobile devices to access all the non-responsive catalog page’s content using the iFrame’s scrollbars as needed.
Hope that answers your question and helps you out.