In that you'll have to go over the list of CSS (inline or files referred) and try to exclude them one by one, as one of those is causing the minimizers (both the default and legacy one) to fail. Once you find the correct CSS to exclude, everything but that will be optimized.
Regarding JS optimization, as stated in the FAQ, given your site's reliance on jQuery the first thing to try is setting "look only in head" and "force in head" options, can you try those?
frank