Excuse my horribly spelled title it was just to get your attention.

I see you've changed permissions on viewing some mods, and it makes me sad..

I came here to download great mods and play them I believe I already got one of them with halo 3 style weapons (Which ARE AWESOME!)

I would just like to ask why are none of these good mods on the nexus?
Do you have issues with them?

Nexus will not host mods that has content from other games. If any are uploaded, they will be pulled down pretty quick. It's done to protect the site and not have lawyers and DMCAs all over their backs. Using content from other games is a grey area and can be considered illegal. Nexus chooses not to touch the grey area at all.

There are plenty of public mods here with ported content that you can still download. However to get the better ones you need to work your way up here in the community. The permissions is a hold over from the VGU days where leeching was a big issue. Now it is a demonstration of trust. Many people will download the content and the release it elsewhere against the Mod Creators permissions. Once again, the grey area. By locking the mods away behind a wall it further protects GUN as it is not easily accessed.

If you want access to the better mods, gain our trust. Be active, contribute, post meaningful thought out posts, practice the golden rule, and you'll eventually get promoted. It will take time, be patient. Remember post count, length of time here, and reputation won't necessarily get you promoted. Quality over Quantity.  This is a great place to be though and mods aren't the only thing offered here. Some great people inhabit these forums. Get to know them.

As the saying goes here, come for the mods, stay for the community.

I'd like to build on what Evmeister said.

While it's debatable the 'better' mods are locked behind a membership wall, some mod authors choose to lock their own mods behind it. The reasons for that you may agree with or not, but include bad previous experience with public mods, minimise publicity or expect better feedback from members who have established themselves.

The Nexus is a much bigger site, which draws a lot more attention from everyone. The ports performed here are at best 'grey' or worse a breach of contract (with a few exceptional cases), and thus to minimise accusations of this, the Nexus has a blanket ban on such mods.