I've got a full blown Zeo system and I have no problems w/ Alk swings. Ca & Alk is dosed using 2-part on a doser. My daily Alk and Ca is metered every 1/2 hour, 24 hours a day for a total of 48 dosings.
I can't neither comment of the ease or difficulty of the Ultalith method nor can I elaborate on similarities to Zeovit.
The trick to running a Zeovit system is to start slow. I've got all the additives as well. IMO, the additives alone are woth trying, especially Coral Snow, Coral Vitailizer, Amino Acids, Sponge Power and Pohl's Xtra. Start low, at 1/2 dosages.
Diatom blooms are common on Zeovit systems, and possibly on Ultralith. WHen this happens, cut dosing additives and add Chaeto, Gracilliara or a similar macroalgae in a lit & cycled refugium to soak up the excess nutrients.
FWIW, my Alk is ~9 to 9.5 dKh, tested on an Elos kit. My SPS coloration is great and growth is unprecedented.
It's not very intuitive, but requires research and understanding of what's happening and how to manipulate trends in a reef.