shoot I always hit post before i remember to add the link...sorry
http://www.marvistavet.com/html/body_inhalant_allergies.html
heres another site to do some reading on, as you'll see it begins with mostly info on dogs and allergies...however most of it also retains to cats as you will read. food or inhalant allergies can bring on many skin issues no specific mention of on the nose but certainly the face....what type of food are you feeding? change that for a trial.
also are you using chemical/scents of any kind in your home? cleaners, sprays, hairspray, cologne, scented candles, scented litter???? stop all chemical use also as a trial.
this looks very painful, you do really need to find a way to take this kitty to a Vet...I've read the suggestions on the link above, and I agree with SOME of it. for instance Esoinophilic granuloma or (EGC).this being an auto immune condition usually due to ALLERGIES, but doesn't usually appear on the nose like with your kitty..... if you are advised to use steroids be very cautious....3 treatments at the MOST within a years time...usually steroids will temporarily clear the affected area but until the actual cause is found it will return, and steroids cannot be used on a permanent basis, they will only treat the condition not the cause, and can lead to diabetes in cats or other serious health issues...
I will send you some info on this skin disease. but please find a good Vet and take this poor kitty in...:) it can be due to many diseases or yes even cancer bottom line being this kitty needs some help NOW...topical ointment isn't doing anything to treat whatever this condition is. I will keep searching for more info and will post whatever I find, please also keep us updated.....
http://www.petplace.com/cats/eosinophilic-granuloma-complex/page1.aspx
i feel like this is exactly what my cat has as well.
http://en.allexperts.com/q/Cats-1606/2012/8/cat-nose-1.htm
Looks like some kind of infection, which a home applied antibiotic ointment likely won't cure.
See if your vet has a loaner soft carrier, that way kitty won't have a hard surface against which to further irritate his nose.