Hi Isabel
Edited #3 looks much better now as you have got rid of dark parts on the corners and at the edges and brightened the image. IMO if you reduce the highlights just a little bit then the image wouldn't look so dazzling and we would be able to see some more detail on the snow.
Edited #4 looks a bit too bright and you lost some detail on the snow and the trees. IMO you should step back a bit (Reducing the hightlights might help).
I tell you what, learning to use softwares one thing but applying them with the proper strength is another thing. Today I nearly went crazy while editing an image because I was trying not to overdo things. So, good luck all of us