Learn Swedish: Vad snyggt! Nu hänger klänningen framme. - How nice! Now the dress is hanging at the front.

Framme is the positional form of the adverb, meaning something is currently out, visible, or at the front in a stationary way. Because the dress is just hanging there in a fixed spot, we use framme. If someone were actively moving the dress to the front, we would use the directional form fram.

Why is it snyggt with a -t at the end, since klänningen is an en-word?

In the exclamation Vad snyggt!, the adjective isn't describing the dress directly. Instead, it describes the general situation of the dress being out on display. General statements and abstract situations always take the neuter -t ending. If you wanted to describe the dress itself, you would say Vilken snygg klänning! instead.

Does framme always mean at the front?

Not always. While here it means the dress is hanging out where it can be seen, framme is also heavily used to mean arrived at a destination, such as Vi är framme. The core idea of framme is that something has reached its intended target position and is now stationary.

How do we know if hänger means someone is hanging the dress up, or if it is just hanging there?