use arrow keys to move forwards and backwards through the sprite not a band btw non-canon so at least for me, the dotted outlines render weirdly. the version of the dotted lines you see on the outside has twice the number of lines as there is when you look inside the project. I actually used a mod of scratch to get dotted outlines (without taking a year to do so), and no, it was not Turbowarp. the same thing happened on the mod I did use, so maybe it renders properly on mac. Solution: the one that's being displayed has twice the number of lines as the one that isn't, so the one that isn't being displayed looks the same inside the project as the one that is being displayed looks on the outside.
The idea of using dotted lines to represent the negative space of the negative numberblocks is not original. I don't remember who I got the idea from, but it was based off of mr bond's nb, and i don't think it went to -10 when I first found it not canon to numberblocks, may never be canon