I would not worry to much! 400 MB = 0.4 GB...
... I would gladly give up the space if I could only read the book. I have downloaded it 8 times and still can't read it. I even went to the B&N store.... after a 30 minute wait for it to download, same thing, it looks like it downloaded it but then the "download" icon pops back up on the book cover. GRRRR. Then I spent 45 minutes on the phone with B&N tech support who had me download it again (only took 10 minutes at home) but the result was the same. There must be a problem with the file. They finally agreed to take it off my account and give me a refund... in two or three billing cycles. I didn't even know there was such a thing as an enhanced e-book. I will buy the regular version as soon as I get my $$ back. In fact I won't be buying anything else until the $$ comes back.