As we're coming up to moulting season this is common - and in my experience seems to be more common with ISA warrens & Sussex breeds. As long as she isn't being pecked all fine
Our first hens were rescued so completely understand how you feel. It is a lovely thing to do but it is heart breaking having them for such a short time. Our hybrids have generally lived for about 4 years but its ranged from 9 months to 10 years
Perhaps you could have pure breeds next and then in the future see how you feel about rescuing again?
If you've only had him a couple of weeks, be patient, it takes a while for them to get used to stepping up onto your finger. Does he step up automatically when he is somewhere else e.g. on top of his cage?
Reiterating Sarkymite, what are you feeding them? And it may be just as she's getting used to laying eggs
Are the egg shells soft or hard/firm? Is it just the appearance thats putting you off?
Yay!
I've read in a few places now that (allegedly) Bluebelles can be prone to laying double-yolkers.
When my Bluebelle was young she used to lay double yolkers