Sorry for the delay in response Weldon - I have other priorities at the moment.
I have checked GOG; the Mac version available for download is 2.0.0.4. This is the same version I downloaded on October 21st.
Re. links to Mac user enquiries:
http://goo.gl/nOsnFJ,
http://goo.gl/2sOcgyA post from Wayens reassuring Mac customers their issues will not be ignored:
http://goo.gl/P93yBOA thread related to the bug I encountered. It informs PC users their version is fixed, while containing no helpful information for Mac users:
http://goo.gl/BgbZet(The last post of that thread is mine, and expresses my frustration at spending hours futilely trying to end Day 2 after unknowingly triggering the 'Cazanoux research' autosave bug. After giving up and seeking assistance online (something I wanted to avoid doing) I re-loaded, played through Day 2 again and went to sleep. The next day I upgraded to Yosemite, and lost all save games. Unsurprisingly, my enthusiasm for playing your game evaporated.)
A thread regarding many potential issues that may prevent in game progress:
http://goo.gl/bqyEb6I purchased GK 20th Anniversary hoping to see if I could still solve all the game's puzzles without assistance, as I did in 1993, but due to the presence of these bugs I cannot play with confidence that if I am 'stuck' the fault is mine, and not the developer's. This is why I cannot recommence playing until a patch has been issued. If Phoenix Online Studios have indeed released a patch for the Mac, then someone needs to ensure it is available via the retail channels the game has been sold through.