Omlet have their own forums in the UK, though I'm not sure if this is official or not.
https://club.omlet.co.uk/forum/
edit - Omlet certainly charge enough of a premium to expect their products to have a longer lifespan than their 2 year warranty.
Surely the paint is there to protect the poles from the rust. Honestly, if they think that's acceptable 30 miles from the coast maybe they should be stating their products aren't suitable in these areas.
Not sure why they would expect you to buy another door from them now that you know it...