Can I give a bit of advice, which is to keep your game in much lower scale
Unless blitz does something very weird, I really don't see why. There is plenty of room for scaling without any precision loss, ie multiplying everything by 1000 would give you the exact same result (floats can handle numbers up to near 1e40). When i say everything, it includes the camera range.If there is really some precision loss I'd be interested to see some sample exhibiting the problem, so that I can figure what's going on.
Anyway using 1 unit per meter is really a good advice, makes everything easier to manage.