Macleod is training with the Ibrox club on their Highland tour after recovering from a virus that sidelined him last season.
Gers boss McCoist said: "Lewis was nothing like the finished article when he got this viral problem so he's still got a lot of developing as a player. But it's just brilliant to have him back. The rest of the squad are delighted."
McCoist is delighted to have the gifted 19-year-old available again for selection.
But, as he prepared for a pre-season friendly with Brora Rangers tomorrow, McCoist stressed he would go easy with the teenager.
He said: "Lewis maintained a great level of strength throughout his time out, but we're not putting any pressure on him. It will take him a bit of time to come back, because there will be a confidence issue there as well.
"He's naturally fit but there's a really thin line. We need to look after him, but at the same time we don't want to mollycoddle him.
"The most important thing is that he's been given the all-clear to take part in training and play games again - that's the biggest thing.
"He's looked fine, but I fully expect him to look even better three, four or five months down the line."