Within the Fantasy Battlemaps style, textures that are tiled can be adjusted to whole number increments (typically multiples of 40 or 60 in a 40x40 map) to match the grid.

However, with the Sci-Fi textures that tile this is not the case. They often require decimal sizes to match a standard grid. See image attached where 70.13 is required - 70 will not match the grid across the whole map) and i have others need 56.12.