Global theme issues—sidebar not expanding to correct level/current page not highlighted in sidebar

Hello,

I am trying to use the global theme. I have configured the sidebar to have multiple page trees. The current page is not being highlighted in the relevant page tree*, just in the page tree at the bottom (which I'm trying to hide by adding loads of blank lines because I don't want it there...).
This works in the documentation theme.

Thanks,

Helen

*Update: the page IS being highlighted, but the page tree is collapsed so you can't see that the page is highlighted. The page tree should expand to the correct level (where the highlighted page is...)