Ah i forgot to update this post.
If i am using it correctly,
scheduler.max_active.set = is quite buggy.
For example, lets say,
scheduler.max_active.set = 2
and you add 10 torrents.
2 Would be active while 8 would be in a stopped state. When you try to start all of them, then 2 would still be downloading while 8 would be paused.
Then, either you stop 1 of the 2 torrents, or 1 of the 2 torrents are completed, the rest of the 8 torrents would suddenly become active.