Thanks for the useful feedback, it really helps having a fresh pair of eyes on the case.
I have darkened the main text a bit as suggested to make it a bit easier to read.
I have also had another go with the screenshots, they have come out better due to raising the jpg quality and making the images just a little bit bigger. The downside to this is that the 4 images come to just under 0.5Mb which I’m sure in this day and age is okay.