Home page drop down folders

The little up/down arrows allow the folder to open and close. I found once I closed the "new threads" folder, it remained closed. Open it up OK, look at a thread and go back, it's closed again

Can these settings be updated anywhere ?

Which style are you using ? "Aria Liquid" ? Try "Aria Liquid Open" (bottom left hand corner of the page)

You should edit this setting in your user control panel to make it permanent - otherwise it is just stored in a cookie and could be overwritten.