Well, the shop runs fine, all orders have everything in the right place, with correct taxes. As soon as I use the order editor, things go wrong. The shipping quotes that I see on the left, the top one (coming from table rate) has no tax, and the second one (coning from flat rate) has 21% tax (high level tax). Both shipping methods are configured for 21% tax.
That's why I added the echo lines to check if the right country data was applied, and to check what percentage was set in the quotes. It goes wrong at fetching the quotes. Table rate give 0%.
Even when I hard coded the qoute method to return a fixed number, 22 to distinguish from the configured 21, it still shows 0% for table rate, but 22 for flat rate.
Have to check that again, still can't believe it.. so weird.