Yes, I have redeem key by email. Where in Store?
From the tutorial ():
Using your licence
If you've made a purchase directly from our site (rather than Steam), you will be sent a redeem key by email. This is a special code you can enter to the Scirra Store and get your license. If you want to buy a license for someone else, you can give them the redeem key and they can then get a license from the store with their own name and email address on it.
Once you have entered the redeem key in to the Scirra Store, you can download your Construct 2 license which is a file called c2license.txt. To start using it, simply copy it to My Documents, or copy it to the install directory (where Construct2.exe is also located). Restart Construct 2 and it should find your license. You will know it has worked if 'Free edition' no longer appears in the title bar, and the About dialog will show your license information.