hehe, tis cool sir.
The base colour I used was BONE WHITE, but as the gel00 is a off white ish anyway, im still not sure if I totally covered it lol, I went over with yellow ocre shading and some muted browns, and then white then layering light 01 , back and forth so I think I got it lol.
the darker umber and sienna colours are the ones I was not loving ( as you rightly ask about consistency ) however I think it has worked due to me NOT having a solid UMBER or SIENNA undertone, ive mixed it up and mottled it a lot, but I still noticed areas where it looked like I had missed. the lighting in my parents garage is pretty horrid , theres 1 3x3ft window at the end behind, and a garage door with 1 little overhead light, ive been having the garage door open when its not been raining to try to illuminate it as much as possible, but it has been far from ideal.
sorry that's long winded, yes I has issues with consistency lol, but that was due to the lighting more that the silicone being untinted.
ok I need coffee, I wasted too much energy typing my rambling reply.