Re: padding before note with accidental at beginning of standard measures

[Kieren Richard MacMillan]

Hello, all --

I think I've almost answered my own question:
> Is there any easy way to tweak the spacing of *just* the notes
> which begin a measure and have an accidental on them

I'm using
    \once \override Score.BarLine #'space-alist = #'((first- fixed- 
space . 2.0))
at the end of the measure preceding the "faulty" measure.

Unfortunately, although it now *looks* correct, I get the error
    programming error: unknown prefatory spacing
    continuing, cross fingers
once per affected Staff-measure in the Score.

Is there a better method than the one I'm using?
If not, is this error something I can just ignore?

Thanks,
Kieren.