Translation:The flag of Iceland is blue, white and red.
Talking about flags, I am so frustrated with Greenland. Look at the flags of the Nordic countries and their autonomous regions.
They all have this common motif of a cross centered to the left of the flag's center, but then Greenland comes along and decides, "Let's have a Polish flag with a circle."
No, you're not being stupid, but it's not the same construction.
- Iceland's flag = Islands flagga = noun, direct possessive
- The flag of Iceland = Islands flagga = noun, the English uses a possessive construction that Swedish doesn't have, so the Swedish uses the same direct possessive as above
- The Icelandic flag = Den isländska flaggan = adjective
That depends on the sentence. Often, we have to use less idiomatic structures because whatever we choose as the default translation is automatically picked for the reverse "translate into Swedish" exercise - and given the choice between teaching unidiomatic Swedish or unidiomatic English, that's a fairly simple choice. Did you have any specific sentence in mind?
The course was created by native Swedes. There's really no need to be snide. We do try our best to address issues in the comments, make corrections, take input from native English speakers, etc.