Bar number moves down inexplicably

[David Wright]

Coincidentally with Message-ID: <address@hidden>
> It also seems to move the bar number down. Does anybody know why?
I also have a bar number which moves down for some reason.

The attached snippet shows the problem. Commenting out the \layout
with % {  →  %{ fixes the bar number but I lose my fermatas (both
cases attached).

I'm not familiar with the action of Staff_collecting_engraver,
but I have a feeling the answer/workaround might lie in the page
http://www.lilypond.org/doc/v2.18/Documentation/learning/outside_002dstaff-objects

Cheers,
David.

ferm.ly
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