It seems I'm a special case: I bought SimCity 5 on GMG using a US VPN on March 1st. I instantly got a key. I registered it on my Origin on that same date and the game is there, on my gamelist, saying it'll be unlocked in 14 hours (my region proper unlock).
I hopped on a Singapore VPN and the game, which was unavailable on my regular Brazilian IP, was available for download on the Singapore IP. I started downloading it, but I was getting shitty speeds (around 30k/sec) because of the VPN.
Without stopping the download, I turned my VPN off. I'm still getting shitty transfer speeds (mostly because I'm probably downloading from the Singapore server). However, I'm just downloading the front end (around 200 megs). I'll let it finish and see what is up.
If I reload origin with my Regular Brazilian IP, the game will revert to the "locked" status. You need an IP from the region which the game is unlocked to launch it.
When installing, Origin told me the game uses 12 gigs.