How to insert an audacity file plus a mp3 file into windows live movie maker 10?

I was wondering how you insert an audacity file plus an mp3 file into windows live movie maker 2010. I have tried, but it only allows me to have one or the other. I have exported my audacity file into a mp3 file, so I am basically trying to insert two mp3 files into a movie. I can export the audacity file as something else too, I just need to be able to play both in the movie. Possibly at different times.|||You will need to CONVERT the files to a file type such as .wma