I don't go on here anymore. I may occasionally pop in and fill random trade requests I see on the forums/on fan sites, but the likelihood of me seeing anything on pm is slim. Direct requests from me are even more unlikely to see a response, sorry.
If your question is in regards to using a sprite of mine in a banner or whatever, if it's tied to dragcave feel free. If it is for something offsite, as long as it's credited back to dragcave and/or myself, go ahead.
If your question is to making a hybrid from any dragon I've worked on, go ahead as long as you have the okay from anyone else involved.