There are no currently known issues for the A7A266 relating to the Radeon. There were a few issues relating to other ATi cards, mainly the RAGE cards. The Radeons were not affected. This was resolved by an update to the ALi AGP driver. Ensure that you have version 1.74E.
I have seen several problems with the SBLive, but have not been able to track down what the specific cause is.
The main difference between rev 1.03 and 1.04 is the addition of dipswitch block 5-10, which allows adjustment of multipliers. Previously, only FSB adjustments were allowed, like the A7M266. Also the missing VIO jumper on 1.03 has been corrected in 1.04.
As far as BIOS is concerned,
Version 1005 Final was released yesterday.
The latest BIOS is
1006 Beta 001.