About how to dilute/control the inks: Maybe i don't completely understand Sandy's method, but I disagree with Paul and what was linked to in his post. This is similar to my argument against a 3MK approach with positive prints on paper. Eventhough the dots are small, and even when they are in three or 8 channels, there is still excessive dithering of the full strength inks. I maintain that it is better to use overlapping partitions of different dilutions—whether they are inks on paper or film for darkroom processes.
In talking with Sandy privately he explained how he was making custom dilutions of the three standard Epson PK, LK, LLK inks and creating an 8 ink partitioned profile. I helped another person earlier last year with a similar kind of set up using the Piezography inks (pre-piezoDN) using a manual approach to setting the limits and cross overs. I will be extending those manual tools into a digital negative version of my profiling system for simple/automated partitioning off of measurements of the printed ink calibration images. That would make this process easier no matter how many inks or what dilutions you want to use. They could be custom dilutions of the Epson inks, the old mixtures of the Peizography digital film inks, or their new stuff (i tested Eboni inks for digital negatives and it wasn't worth the trouble). Again, this is not meant to just be a plug for my own stuff, but is more of a comment on the kind of thing you can do when you get into some of the more powerful and customizable features of QTR, and to why I advocate for overlapping serial partitions like QTR can make.