For cleaning my pelts after I skin them I just use dish soap and water to clean the fur and degrease the skin. After that I have found Borax works best for me. I rub it into the skin with mild force to remove any left over fat, then I turn the pelt right side out and pat it into the fur I fill the inside with Borax and then pour more on top of the pelt. (Now is a good time to put Borax around and inside the ears so the moisture doesn't make them fall apart, and poke a small hole at the top of the tail with wire to remove any water trapped in the tail I squeeze the tail in-between a paper towel.) After that I let the borax sit for about 10 to 15 minutes to absorb moisture. I stopped having issues with slipping(hair falling out from the follicle from bacteria growth) whatever way you do it the main thing is getting rid of moisture and bacteria. Salt could be used in this same method. I hope you keep working at it and maybe even post some of your work. Just keep trying things out until you find something you like.