Sorry to hear you are having install issues. I just received Keylab 61. I was able to go through install without any issues. The only problem I encountered was that the install process installed version 1.04 of the Analog Lab software rather than 1.05 (which I immediately installed after 1.04). I am using Macbook, 2.5 Ghz i5 dual core, 16 G memory, OS 10.8.5. The keylab displays version 1.25.
Most of my time so far exploring using Analog Lab standalone...incredible number of sounds, some great, some not, hard to navigate through them all though the filter is a real plus in this regard. I have run using buffer size of 512 as well as 1024 samples ..didn't see much of a difference so opted for 512 to minimize latency. I didn't see much in the way of heavy CPU spikes. With a few hours of use, Analog Lab crashed once in multi mode. I also used the KeyLab 61 with Apple's Mainstage 3 and did not have any issues using Mainstage's instrument set. The Arturia AU plug ins are visible though I haven't spent much time using them within Mainstage nor have I done any controller mapping yet (this weekend :-).