A few days ago my game automatically updated to version 1.5.4 upon opening SCII. Since that time, I have been unable to access these maps and play new games versus AI. I tried the cache flush that was recommended on similar map-missing posts to no avail. I also tried trashing my entire SCII folder and re-installing from Battle Net. Nothing has worked thus far.
I can still log into Battle Net, play the campaign mode, play saved games versus AI, play the challenges, etc.
I am playing on a MacBook Pro with OS X Version 10.7.5