Surface overlays in niwidgets

Dear niwidgets experts,

Thank you very much for developing the niwidgets package. It is exciting to see a surface in a jupyter notebook for the first time! I’m having a little trouble however getting an overlay to show.

Which type of gifti file does niwidgets expect? I tried to overlay a func.gii file on top of a surf.gii file ( https://balsa.wustl.edu/about/fileTypes ), which works in matlab using the gifti package, but I am not seeing the overlay in the notebook.

Lastly, if I want to display a timeseries on the surface (i.e. a 2d surface x 1d time), is it possible to flick through the timepoints, or perhaps create a video using niwidgets?

Best wishes,

Sean