I live in San Diego and have made a few hundred Kallitypes, as well as having taught the process to a few hundred students.
I had to put a humidifier in the darkroom in order to control humidity. as humidity in the paper fluctuates, so does the exposure time. If paper is too dry, the image is weak and will never produce a good d-max. A definite schedule to follow between coating and exposing is a big help in maintaining consistent humidity in the paper.
Clearing is a problem,especially if you don't tone prior to fixing.
The first rinse must be slightly acidic. I use a little citric acid at this stage and it eliminates a good 80-90% of the yellow. The subsequent clearing baths take care of the rest.
Prints should be toned, and this is done prior to fixing in dilute sodium thiosulfate only.
Gold is the traditional toner. If you want it to look like a platinum print, tone with Pt. If you want it to look like a palladium print, tone with that.
Papers are important. Any buffering causes problems.
If you have Stevens book - get rid of it. It has led many beginning printers far from the correct path.