IM currently using a mac and game pops out saying "It appears that your graphics drivers and/or hardware are missing critical OpenGL Capabilitiesf this error persists after updating your drivers and your hardware supports conforming did OpenGL 3.2 support please contact us for additional help Error details: could not find OpenGL extension proc "glDrawArraysInstanced." System specifications Intel(R) hd 6000 1536 MB Ram 8gb 1867 Mhz ddr3 Mac OS X 10.11.1 1.6 GHZ Intel core i5 IMAC 21.5 inch late 2015
It seems OS X 10.11.1 is a slightly older version of OS X. They are up to 10.11.4 by now. You could try installing all of the OS X updates first to see if that helps. Your iMac should have support for 3.2 according to the specs though.
Can you upload a PA log? Instructions on where to find those are here: https://wiki.palobby.com/wiki/Planetary_Annihilation_directory