We filled out the form, saved the file, and emailed it to my wife's mother recently.
Actually submitting it was a bit of a challenge. Since she can't read english very well, we did it with her over the phone at the same time. We loaded the save file on our computer and she loaded the same file on her computer and we walked her through it. We basically went step by step right to the last page, and then she submitted the form and she printed out the confirmation page. It took a while because my inlaws have no idea how to use anything on their computer except internet explorer and skype.
Unfortunately the form still has some glitches. Some things we noticed was that every time you load the file, the "intended date of travel" would reset so we had to type it in every time. Also even though we didn't have a photo to upload, we were unable to get past the photo page without one. We had to upload a blank JPG file and once it got rejected, we were able to go on to the next page. And lastly the form would occasionally time out on us due to inactivity even though we were actively typing. So save the work to a file often.