Need to convert .mix files to .jpg quickly and without needing PictureIt? I figured out the easiest way to do it:
1. Have the said .mix file saved on your computer somewhere. "My Documents" is easy enough since it'll only be temporary.
2. Open up Microsoft Word and click on the "Insert" menu.
3. Click on "Picture" and then "From File..."
4. Find the .mix file that you have saved on your computer and insert it into the document. Now you should be able to view the image as a part of your Word document.
5. Now, in order to save it as a jpeg, just go to the "File" menu and click on "Save As."
6. Save the document as a "Web Page" (again, let's say in "My Documents")
7. You won't notice anything different, but then go to where you saved the web page document (in this case, your "My Documents" folder) and you'll see that there's the web page file along with a folder titled "filename_files." Open this folder and inside you'll find the .mix image saved as a jpeg. Then feel free to rename the image and place it wherever you'd like.