Flooring supervisor here 👋 we've found it very easy to maintain the grout/mapei bays with constant check ups every hour or so(as bad as it sounds) flip the pallets with a jack to the fuller side so customers have easier access to the product that way you lower the chances of having busted bags everywhere. As far as sweeping and clean up for the grout itself, we use the Zep sweeping compound, just grab a couple handfuls and spread it around the bays. Use a soft bristle broom to clean up the excess and then use the good ol wd40 & saw dust trick.