Thank you guys for your comments.
Actually I am an experienced C++ programmer. I feel tired all these years using this powerful programming language. Recently I found the Construct and I am very impressed when looking to its functionality and the easiness of its use.
To be honest I am thinking for a simple game. The Alien sprite is a 'product' of these thoughts. I've done many efforts in 3D but, besides all my efforts, I could say that I am not talented in concept design and 3D modeling. If I go to 2D through 3D then I will have to pay for the models which are not unique also. I feel more comfortable in direct 2D and Construct now is giving me the chance of building some simple games with my own 2D resources.
Although I feel very comfortable with the criticism I've received for setting up a small fee, I still believe that 1,00? is not an amount which is specifies sales. Perhaps I did a mistake. I don't know. Any way, you can download the files of this sprite from the links bellow:
I hope someone will use it (in any commercial or non commercial project) and enjoy.