LRTimelapse mode - Not able to click "Aperture Ramping"

[Novelectro]

Hello,

I've been trying to figure this out for a few days now but to no avail. I want to be able to ramp my ISO, shutter speed and Aperture for a day to Milkyway Time lapse. When in the LRTimelapse mode of DSLRDashboard I go into settings where I see the "Aperture ramping" box, but it is not clickable. I'm using a Nikon D750 with a Sigma Art 35mm f1.4 lens and DSLRDashboard on my Samsung S8. It seems that every other aspect of LRTimelapse in DSLRDashboard works, so I'm not sure why the box would be unclickable.

Anyone have any ideas?