I'm assuming that the instance has associated cdf parameters. If you change the value of these parameters through SKILL, you will need to manually trigger the cdf callback for that parameter. As an example:
inst = dbCreateParamInst(your_args_insterted_here)
cdf = cdfGetInstCDF(inst)
cdf->fingers->value = 12
I hope this gets you what you need. BTW, the default cdf values are stored as cdf->fingers->defValue.