Mac: no context menues with trackpad instead of 2-button mouse

Mac: left click + ctrl instead of right click don't work in muse score.
I upgraded my iBook with Tiger to use muse score (fine, no dongle, and it works on a G3 :-) but I can't use the context menues in muse. They work in muse with a two button mouse, and in other programs as they should, but not with the trackpad or a one button mouse. (Same on my G5 desktop computer, it's no problem of the IBook.)

This makes it impossible to do serious work with the notebook.

Originally posted on "Support & bug reports"