Template Studio - adjusting tick marks on vertical scales

I am using the Depth Related item "Vertical Scale" in Template Studio to add depth and elevation scales to report with a graph. I can adjust the spacing of grid lines for a given plot, but is it possible to adjust the spacing of the Long, Middle, and Short Markers in the Vertical Scale data item (which serves as the master vertical level for the entire report)?

The wiki says that a Long Marker is placed every one depth unit, Medium every one-half depth unit, and Short every one-tenth depth unit. Can any of these spacings be altered?

The attached image illustrates the issues I am running into with my report.

Thanks for any help you can provide.