Is timeframe the only thing you have a problem with? We can say it took a few more years, just not thousands, because that's ridiculous to say that they'll exist on the planet for thousands of years and still be in medieval stages.
As for the world and how they live, just assume that it's got a hell of a lot of livestock floating around the place, not to mention fish and of course edible vegetation. Ingmarians don't eat much in the first place as they gain energy from sunlight as well as food - you don't get much food in the deserts of Aiyon, let alone water, although they still do keep drinks with them if they can.
You put a family on a resourceful island for a couple of years and if they have the knowledge, they can build themselves a house and breed chickens and eat the fruit. There won't be every single person from the medieval ages, it's not going to be a hugely populated world at the beginning, just spread out, that's all.
I'm happy to change the time for nations to come into action, though, if it suits your personal mindset. |