Apologies for the lack of updates recently.
I was hoping that Mac OS X 10.4.9 would have been released by now, and we could see if it fixed Mac support the GPS-CS1. It's still in beta (developer seeding) though there are signs that a public release could be imminent.
Yet another new build has been sent out to developers, and there are two hints that it's nearly ready. First, there have been very few fixes between this build (8P125/8P2125) and the last one - and there are no known issues this week. Second, this is the first version that's been sent out to non-developers. It's gone to ordinary customers who are part of Apple's customer seeding program.
If anyone, developer or customer, has 10.4.9 and a GPS-CS1 then they won't be able to tell us if it works because of Apple's confidentiality agreements. However if you are one of these people, if you test it and it doesn't work, please can you report it to Apple?