No problem with the use of potassium dichromate to sensitize the Carbon Tissue BUT
I make myself my Carbon Tissue for use in 8 days
I always use fresh potassium dichromate
I do not include potassium dichromate in the formula of carbon tissuer
I cupped awareness but still the same concentration, the same temperature, the same time awareness, the same drying time, the same humidity
I use always the same formula of Carbon Tissuel in eight days of its manufacture
I always use the same kind of digital negative with Software appoints an application that I created for Carbonl
My exposure time is always the same, I confirm

This just to say my personal experience but I'm just practicing as a small amateur photography Carbon