[MU4 Issue] Problems with measure rest and multibar rest width

[its-not-nice]

In this score (3x 3/4 bars followed by a 4/4 bar, repeated) turning multirests on (press 'M') demonstrates a few issues:

Most obviously, the first system is escaping its bounds.

Secondly, the multirests are narrower than the single bars, which is very confusing. A single bar may be as narrow, perhaps, but shouldn't be narrower.

Lastly, the first 3-bar rest in each system is wider than the others, presumably because of how the system header is/is not accounted for in the calculations.