I’ve just assumed so but never had it confirmed - is this light blue are indicating z-compression, that the resin will flow out there or what exactly does it mean?
Good question! This is not related to Z-compression. As far as I understand, the blue shaded region indicates the upcoming layers of your model. Because models can have a finer resolution than the layer height of your print, the shaded region shows a feature of your model that doesn’t exactly match up with the layer thickness. When advancing to the next layer, you should be able to see that region be filled in.