Quote - This update was mainly for Mac users. 6.3 is primarily code rewriting for compatibility with Mac OS 10.6 Snow Leopard, with a lot of minor tweaks and bug fixes for both the Windows and Mac versions. I am sure that they have given it heaps of beta testing.

I wonder ... It certainly keeps crashing on PowerMac 10.5.8 Leopard ... And my Mac won't run Snow Leopard. I'm still using version 6 as every upgrade since has failed to work on 10.4.11 Tiger.
Let's hope this is just a test version and that version 7 will be the real deal!