Acknowledged, this is a known issue with the “Row Gutter Size” property and we’ve got it on our list of things to address. The workaround is to remove the “Row Gutter Size” property — I noticed in your example you have it set at 10px. If you remove the 10, then this won’t happen. Unfortunately you don’t get a gutter between divisions when your divisions have to wrap to separate rows, but at least you don’t get the weird horizontal spacing.
Thanks. That’ll work now.
It’s not often the responsive capability of the grid will be used all too often anyway. So not much issue with row gutter size 0px.