HD: Haunted Island Beta Forum

I could upgrade it right after I built. I tried it later but if I click at the building nothing happens (also I'm not sure what it supposed to do so I can't really tell if it's working ).

I had the same problem but then when I clicked in the bluiding site (with flames and stuff) and I could choose to build it. I did it, the vault is there but the game still says I have to unlock.