Time-measurement is an interesting question. Their year would only be about two months long. These revolutions would be the crux of any calendar.
true, but how would they know that they have made a revolution? There wouldn't be any seasons or animals migrating or anything they could discern that would indicate a completed orbit around the star. Maybe the moon/moons are the answer to this as well. A Solar eclipse would be pretty interesting for people that know no darkness.

That comment reminded me of an interesting piece of information I read in Jared Diamond's book Collapse which could be relevant to this world. He spent a lot of time on an island in the Pacific called Tikopia which is particularly isolated, with next to no contact with the outside world even today. The island they live on is so small that they can see the ocean from almost any spot, and that they're all intimately familiar with every square meter of the place. They denote direction in relation to the ocean - for example in one instance that Diamond witnessed himself, one islander told another that they had some food on the oceanward side of their face!

If the sun is completely stationary in the sky, the inhabitants would be likely to behave in a similar way to this I think!
Good point! I would imagine where ever you were the sun would be "north".

Also I think they could use the rings of vegetation as terrain reference for how far away from the sea they are.