I use the spacer as well to fit my neanderthal eyebrows in the headset.
I played around with the left/right only setting a little bit and it appears the right eye causes the jump to the bottom right when blinking.
The left eye appears to mostly work but it has trouble reaching the bottom, I need to look a little bit into the dark area before the eye tracking goes further down. Which would explain why I sometimes can see the foveated streaming.
Not sure what causes these issues with my lenses but I wrote them a mail about it and maybe they can swap me to the eye-tracking variant since they promised working eye tracking on the Frame.