TWRoO on 29 August 2012
Yeah that was taken down with the old gamrreview database... it was still up in the background for a while (only links to it from VGC were through the "Around the network" links below the comments on a games sales page) which is how I managed to add Wii Fit and Nexus to my collection a couple of months ago, but since then links are now redirected to the new gamrreview site or gamewise.
EDIT: wait... you managed to add some games but not others? I would think the only way to add a game to your collection now is to have already had it in your wishlist section... otherwise where did you find the button to add it to your collection?
