Here's what I do:
1. I download the file to my desktop. It arrives as a folder-looking icon with a zipper down the middle.
2. I open the folder and move the file within the folder to the desktop.
3. Next, I delete the folder leaving the file (that was once inside the zipped folder) on top the the desktop.
4. Right clck the file and choose "Rename" and change the suffix from .xxx to .zip.
5. Double click that folder that was created and all the .bmp files are there.
6. Move the files into the NevoStudio gallery area