Allah is the Arabic word for God. I’m from Indonesia and in our bible translation, we use the word Allah for God.
In respect to Muslim’s understanding of God, I tend to compare their understanding to how the Israelite understand God during their journey in the wildernes/desert. The Israelite saw God as the punishing and harsh God i.e. Moses ordered the Levites to slaughter the Golden Calf worshippers.
We Christian has been visited by God Himself through the birth of Jesus Christ and more have been revealed about the nature of God to us than Muslims. We know that God wants a closer relationship than a mere Master/slave relationship, but Father/Children relationship. Jesus is the Firstborn i.e. we are the younger siblings trying to be closer to God.
Let’s just pray that Muslims (or all other religions in the world) could be invited to a closer relationship with God like the one we are graced. Afterall we are all the sons of man trying to redeem ourselves to be the sons of God - the heirs of the Kingdom of Gods.
PS: thanks for the article link from The Rock.