This is by no means official

daal wrote:
1. What is an "active topic?"
a topic that is read by a lot of other people
daal wrote:
2. When clicking for example "View new posts" a page appears with various symbols on the left. On the far left is something like a circle with a page in it. Sometimes the little page-like thingy is white, sometimes yellow, sometimes it is moving. What does this indicate?
white - you've already read everything there
yellow (or orange) - there are new posts that you haven't read
moving - active topic (see #1)
daal wrote:
3. On a list of posts such as mentioned in question 2, some posts are dark blue and some are light blue. What determines this?
good question... don't know
daal wrote:
4. Some folks have spoken of a feature called "mark posts as read." How does this work?
if you view forum subgroups as a whole (instead of all the latest new posts), then you may see several "orange/yellow" topics that you haven't read yet. If so, then there should be a link to "mark topics read" that will flip them from yellow/orange to white
if they are all white already, then the link won't be there.