I think that the dialogue for setting the crystal to prevent/allow death might be backwards. In `statstab.gd` the following block occurs. I believe the first block should probably be for `preventsdeath == false` and the second block should be `preventsdeath == true` I switched them for the crystal visit section and it seems to have worked.
if globals.state.mansionupgrades.dimensionalcrystal >= 4 && globals.state.thecrystal.preventsdeath == true:
buttons.append({text = person.dictionary("Use the Crystal to Prevent Death."), function = 'crystalimmortalitytoggle', args = 'enable', tooltip = "Use the Crystal's power to prevent death in your Mansion."})
elif globals.state.mansionupgrades.dimensionalcrystal >= 4 && globals.state.thecrystal.preventsdeath == false:
buttons.append({text = person.dictionary("Remove the Crystal's hold on Death."), function = 'crystalimmortalitytoggle', args = 'disable', tooltip = "Re-enable death inside of your Mansion."})