Congratulations on your new machine. I love my 350E! When I first got it, I had the same problem--because my thumb drive was not formatted. Here's a link to the Janome forum on this topic--the second post gives detailed instructions on how to format the drive. It is very easy.
http://content.janome.com/fusetalk/f...&enterthread=y
Emblibrary is my favorite site for designs! Kenny has an excellent article on organizing designs at this link:
http://www.emblibrary.com/EL/elproje...log=Elprojects
Unzipping the file is easy: right-click on it, then click "Extract all". But when I download from emblibrary, I just download the unzipped version. I also click on "PDF" under "Color Sheet", and save the color sheet with the unzipped "jef" file. (When I am ready to actually do the design, I print out the color sheet and mark my thread choices on it for future reference. I use Madeira polyneon thread, so I use a conversion chart from Janome to my thread colors. When I am finished with a design, I file the hard copy of the color sheet in a notebook.) Also, when I order a design, I click on the picture of the design, and right-click on "Save Image" and file that picture with the "jef" file and the "PDF Color Sheet". I make a separate folder for each design, and then file them in categories similar to the design categories at emblibrary (i.e., flowers, holidays, children, etc.). I have an icon on my desktop that takes me directly to all my embroidery files.
To copy a design from the computer to the thumb drive, right-click on the "jef" file, then click "Send to" and click on the appropriate drive.
A word of caution: Never put the thumb drive into the embroidery machine before the machine is turned on--it will erase the contents of the thumb drive. Ask me how I know that tidbit of information....
I hope this helps. If you have more questions, don't hesitate to ask! Good luck and enjoy your wonderful new machine.