Friedemann, you are being a little dogmatic, absolutist, black and whiteist so to say. ( dare I say “again”?)
We often forget words, even in our own language. We get things rights sometimes in a new language, and get them wrong at other times. No big deal.
As for framtid (future) in Swedish, yes I hesitated over this word. “Fram” means forward, but for some reason when I retrieved from my memory the name of the book and audio book by Herman Lindqvist, called “Från Istid till Framtid” (from the Ice Age to the future), my brain suddenly told me that the book must be called from “the Ice Age to the present”, and that thought overruled, in a split second, my instinct to say “the future”. No big deal. There are always moments of hesitation, and we nail it sometimes and for some strange reason not at other times. I can assure you that I had no trouble reading those books, and even talking about them.
Peter, I use QuickLingQ and we are working to make the LingQing process even easier, no promises. BTW, for Czech I use a lot of google translate since there are few user hints. I find that the interest in the articles sustains me. I am now reading books on history away from the computer and enjoying it, although there are perhaps 15% unknown words, which I occasionally look up if they really bother me.