There is a free download for Iclone 5.  I've registered and recieved my serial number about half an hour ago.  However, I keep getting an invalid serial number error when I try to install. What am I doing wrong?  I'm copying and pasting the number directly.

Where did you downloaded your version of iclone 5.
To the best of my knowledge on the www.reallusion.com site it's only possible to download a free trial version without serial number.
To have a serial number it is necessary to buy the software.

It was on the site and it was most definitely free.  But its not the latest version its version 5. something.  Offered through digital downloads daily freebies.  Its working now, I put in a support ticket and it taken care of. But thank you very much for your reply! The daily digital downloads has some really crazy free offers but they are usually only good for 24 hours.  Anyway, thanks again and have a great evening.

Well pleased that everything is going well now.
I wish you a good fun with iclone 5 :)