I need a little help here from renderman Gurus in this forum. I've a problem here. I'm actually doing a research on creating realistic skin shaders here. Everythings fine when I'm playing with alot of the advanced features in shading the models. I'm especially happy with the result of using color spline to control the amount of blue in highlight and redness in dark area. But things getting messy when i'm just trying to make a simple layer shader from 2 shaders which already have bump value. This just doesn't make sense in such an advanced renderer (or maybe i'm too dumb to use it). However, i'm not a programmer. not really sure whether i'll understand if someone just throw me with a solution totally in codes.
Here's some screen grabs of my current situation and I hope this can give everybody a clearer view on the question i'm trying to ask.
Here's my workaround