When do they let you register ?

What's with the invitation codes ?

Why not just let everyone register when they want ?

If anybody has a invitation code, I would be grateful!

Answer:
Check your email
Answer:
You missed 3 open registration days at the beginning of the month.

I'd continue checking http://demonoid.com EVERY day for the next ones.

Please try and keep your share ratio around 1.1 when you get in.

They stopped penalising people for having a low ratio because the stats were found to unreliable due to dynamic ip addresses and other reasons which I'll skip. I concur that this has had the affect of allowing more leechers on to the site.

People with low ratios will not be respected or helped out on the site nor will the be able to create invites.

Answer:
they’ve invite codes and limited registration to keep the leechers and spammers out. as well as code kiddies who share false stuff.
Answer:

You could try http://www.getdemonoid.com/

Personally, I like Isohunt