Created attachment 424610 [details, diff] patch for lyx-2.1.4.ebuild Ugly hack to install lyx-2.2.0_alpha2 against qt-5.6
Created attachment 424612 [details] lyx-2.2.0_alpha2.ebuild
I incorporated most of your changes to lyx-2.2.0, check that is works as intended for you.
Dear Pavel, Lyx-2.2.0 installs correctly and I have tested a pair of small documents successfully. Thank you for bumping.