2 ?'s for you. First what color apoxie sculpt do you use? Second when did you use the oil paints? I'm assuming the oil paint is burnt umber, titanium white and ivory black that you used on the nodules.
I use the Natural Apoxie Sculpt. I use the oil paint right after the acrylic. The acrylic dries very fast. You must have overlooked it...On the fourteenth photo down in the tutorial I list the three oil colors that I use. Hope this helps.