Hi, i would like to dig out the topic a bit
In my opinion that manual adjustment option should be built into that preset - it has been more then 3 years now and it isn't changed!
However, I have the same issue with "Small Plain Tiles". I tried to reproduce the same technique, but I cannot handle it :/ Could You please explain how to modify that preset or make the one with that additional options? I need to use plain tiles with different dimensions very often and it's always pain in the ass to make them manually