Arpeggios incorrect

I'm trying to get an arpeggio to activate properly thru both hands of a piano chord. After installing according to the way described in the manual, which didn't work as expected, and trying to tweak the notes and the arpeggio symbol, it still won't work. Here's the image in the score in Continuous View:

Of course, the arpeggio needs to cover both staves (this is a compressed grand staff, but the hands are dictated by the stems). Tried using the Piano Roll, to no avail. Is this a bug, or is there a way to get the arpeggio to work properly (without a convoluted workaround).