I played hundreds of skirmishes with the computer in expert mode and FFA, several online games with 3 human VS 4 or 5 computers, and I NEVER had as many difficulties as with this mod!
In the last 10 skirmishes with WOL, I've been attacked by four or five different computers, several times, in the first 15 minutes! And always with strong and numerous troops!
What makes the game too hard (and unfair) is that the computer tracks all the workers, even the most backward or hidden in the map, even when they are moved long distances. It looks like the computer has no fog, it sees everything as if it had sent spies all over the map.
Personally I do not enjoy playing with expert computers in these conditions. You only defend by ruining yourself, you resist, resist, and it's only after an hour that you finally manage to really attack the computer in its base.