No got key by UbuntuSoftwareCenter

[primax]

Hi all,
in halloween my friend and me bought Amnesia...my friend is a fedora's user....so he bought Amnesia by Desura website and he got key-serial and a section where download Amnesia's client for windows, linux and mac.
Now...I am an ubuntu's user and I've bought Amnesia by Ubuntu Software Center, but he installed the game in my os and he didn't give me a key....and a website with sections for download the clients for install Amnesia in my macbook.

So...What should I do? At least for the key-serial.

Thank you in advance.

PS: I have a document who certificate I have bought Amnesia.
PS: Sorry for my bad english, I hope you all understand.

EDIT: pardon me....I saw just now in the section dedicated to linux.