You cannot, that's the issue with doing it that way IMO, and why I suggested you consider a smaller grid. You can always make tile 2x2 (or 6x8) but you cannot make them smaller than 1x1 (-50% is not reducing the size of the grid, just the space the tile consumes).
Enough time, and enough money ANYTHING is possible!! That my motto and it aint changing!!
Yes you could make the dimmers switches but then you would only have off/on. No dimming control.
Have you seen the new smartly mod for dimmers? It puts a slider and switch in a one row tile.
Pretty neat stuff. I haven't changed my Lighting dash over to smartly 2.0 yet, but these tiles are one of the things i am looking forward too when I do. I hope to be getting to them soon now that it's gotten colder out. Time for inside chores!