fixed vertical spacing within staff-group

[Eby Mani]

Hi,

How to set fixed vertical spacing within staff-group ?. 

I have tried the following in \layout { \context } section. Vertical spacing 
keep on varying if there are beams, ledger lines or cross-staff notation. Even 
tried with padding=#0. Without the StaffGrouper, spacing is somewhat ok(but i 
feel little more spacing is required), except the cross-staff part.

\override StaffGrouper.staff-staff-spacing.padding = #2
\override StaffGrouper.staff-staff-spacing.basic-distance = #6

examples attached, compiled using the above settings, for some system the 
spacing is correct and for others it is either excessive or less.

Thanks,
Eby

excess.png
Description: PNG image

little.png
Description: PNG image

ideal.png
Description: PNG image

excess-cross-staff.png
Description: PNG image