I'm pretty sure you're not allowed to double post. If this map has a night and day you have to make it so the night comes at a certain time during the game. You can't just post the same map twice with different filters...You might want to check with someone on that, I'm not sure.
I'd suggest combine the two threads and just have two download links at the bottom of the thread. Just a add a blurb in the map description about the changes between the two different versions. There isn't much point in having the two separate threads because any discussion about one map will almost certainly apply to the other (since they are the exact same map).