floyd,
Out of curiosity, have you tried "Options | Reset to factor settings"? I find that this is often a useful tool when BIAB stops doing things that it used to.
Another thought...
The "Band (on dbl click)" option in RT Picker allows doubleclick to select the solo RT (if the option is de-selected) and the RT with a band (if the option is selected). I know that you are aware of this.
What I've sometimes found is that it is occasionally useful to give some settings a bit of a nudge. For example, what I'd do if this was happening to me would be...
1. If the 'Band(on dbl click)' is active, de-select it -- or vice versa
2. exit RT picker
3. exit BIAB (so that preference files are update with new choice)
4. restart BIAB
5. go back into RT picker and return the Band (on dbl click) setting to its original setting
Regards,
Noel
I have not tried Return To Factory Settings.
I did try the rest of what you suggested - without any change.
I also get the error if I press the Play or Stop button in the RT picker...