Hi bbilgefoyle ,
You can change the Settings here:
I myself, find it easiest to Add the Reference Image when in the appropriate View (so: in Top Orthographic View, when Adding the Top Reference, and so on),
then the Depth and Side make the most sense to me.
Thank you very much. It seems like "Only Axis Aligned" feature not working as I expected, also have to change the side settings. Kudos!