Hi gemma,
It looks fine. Next time, up your rennet to 0.8 ml. You had a floc time of approx 20 minutes, so cutting around 70 minutes post rennet would give you the 3.5 floc multiplier that I used. You're just over 4x. No major problem there, but you should have a moister cheese that will age more quickly. However, as this is not a long aging cheese (ready in 2 or 3 months), the difference in aging will probably not be noticable.
Anyway, it looks to me that you're on the road to a really good cheese make here. White mold will be fine, and the rind may darken up (go orangeish, etc) if you get some b.linens taking up residence. Fight the black spots as best you can (lower the humidity if you're getting many of these; once the geo - white mold - takes hold you'll have less of a problem with that). The black spots do not go deep in the cheese, and tend to be on the surface. So, although unsightly, they are not a problem.
I think you're going to be very pleased with this one. It looks like you're bang on track. Well done.
- Jeff