Example bmu2.tex not working with bmx

[callegar]

Specifically, case 5 does not work: the bold \alpha is not printed at all.

[davidcarlisle]

thanks for the nudge, unicode-math (and luatex, and to a lesser extend xetex have all change since I last really worked on this.

I'll see if I can resurrect a working version and work something out with @wspr on best way to work with unicode-math