Hi,
not sure, if you found your answer. I had the same problem. First of all, tan-kote is not the best resist to use. I tried resolene, which actually did the job better but not the best. I am planning to buy Pro Resist to try it out.
Tan-kote is not waterproof which is quite bad when using a liquid gel. Try using an antique paste. Gel will most probably penetrate resolene as well.