Yes!... Sorry it took me so long to write back too!
In Islam Jesus IS separate from God. In fact, not all Christians believe that Jesus is God. My mother who is a Christian was very surprised when I asked her if she thought Jesus was God. Other Christians I talked to had the same reaction. Islamically Jesus was a messenger from God, a prophet.
No, you are quite right. The injeel is not the same as represented in the bible and even the deciples didnt write tem as they are in the bible. They are just 'according to' Matthew, Mark, Luke and John some written almost a century after Jesus.
Interesting that you say that Jesus claims to be God. My study of the bible proves otherwise. Can you state where you found these claims? I would be interested to know.
The origin of the injeel is from God Himself. It is part of the Word that God has created. He sent the Injeel to Jesus.