Vitamin E oil, vaseline lip balm, dove deep moisturizing lotion.
These are what we use. Vit E for my husband, lip balm for my son (5 yr), and I use elidel/metrogel/dove. Two are scripts for my thyroid aggravated dry skin and other issues. A little grease is perfectly acceptable and actually improves the mask seal in my families opinion.
MOJO has a full gel face mask. It is moldable. You will either like it or not. You might want to check with your respirtory therapist and see if they have one you can test.