Pretty sure the original post was referring to the "NextPrevNumericAndAdvanced" pager option...and not just the "Advanced" pager option. If you look at your demo page with this pager option... and slowly shrink your browser width to simulate other viewports, you'll see a few bad things... 1) the "Item X to Y of ZZ" seems to be right justified (float right) and DOES "bleed" through everything as the viewport shrinks. 2) Nothing gets stacked, removed, or shifted to other lines the way you might expect (at least) in a bootstrap design/skin. Therefore, you have bleeding at best and complete overrun outside the grid boundaries for everything else at worst.
At least for the bootstrap skin, I would expect that to be very fluid and stack the elements as the viewport changes... NOT become completely unusable and cram everything into one tiny line if there are enough pages that fill up the area and/or the viewport is small to begin with. People want to use ONE pager design through an application (presumably the one with the best functionality for their app)...and the number of pages and viewport shouldn't play a part in that decision. As it is, we either have to dumb-down our pagers to accommodate the most demanding situation (however rare)...else, go through media query hoops to remove the pager pieces that are screwed up at the lower viewports.
It can't be that hard to make things less (one line) rigid and instead to make things fluid across many lines as the viewport dictates.