I have tested extensively with an UIA-11 receiver under Snow Leopard 
and couldn't find any problem. It works really fine here.

Please provide me with this information:

1) Have you rebooted after installing the new driver version 1.6.0?

2) Have you tried attaching the receiver to a different USB port on 
your computer?

3) Does the receiver show up in RB > Prefs > Hardware? If yes, what 
exactly doesn't work?

4) Please also send a System Profile in SPX format (=> you can create 
it by running System Profiler,app and selecting Save) to info -(a)- 
iospirit , com, so I can get an idea of what your system looks like.

Best regards, 
Felix Schwarz