I'm playing in a campaign where we have decided to adopt the Slow Natural Healing option, where a long rest does not put you back to full HP, and you need to use hit dice. I can't figure out how to do that with the Long Rest button so that it resets all my spells slots and limited use abilities without also refilling my HP. Am I missing a setting somewhere, or is this not currently an option?

Quote from Rhodry_M >>

I'm playing in a campaign where we have decided to adopt the Slow Natural Healing option, where a long rest does not put you back to full HP, and you need to use hit dice. I can't figure out how to do that with the Long Rest button so that it resets all my spells slots and limited use abilities without also refilling my HP. Am I missing a setting somewhere, or is this not currently an option?

 
Not currently an option due to the Slow Natural Healing option being an entirely optional and seldom used rule. 

I think the only difference is the health so before long-resting record your health, and work out what it would be after long rest - then use long rest button and just, well, apply damage damage to get your health to where it should be. This is still a lot faster than pen and paper.

Ok, thank you