I want to buy Linux version

[aniruddha]

Well I purchased it, downloaded it, and ran the installer, but when entering the serial number, I get an error:
"Please Enter a Valid Key"

I have entered the key as the straight 16-character string I was sent, and also with hyphens every 4 characters as it shows in the dialog box, but I still get the same error. I have tried numerous ways: copy/paste, hand-type, lower case instead of upper case, with and without hyphens, etc. I even tried it on another computer with the same results.

My computer runs Ubuntu 7.04, and the install directory is one that I have full permissions to.

Are others having this issue with the Linux version of Penumbra?

Yep. I followed the same procedure you did before mailing support. Disappointing.

Same problem here. I emailed support yesterday and they replied really fast. I am confident they will fix this soon.