Official Tournament Map (TE remake) Thread - Tiberium Essence Fans

So, seeing I enjoyed playing TE a lot and did some modding in the past, I figured I'd try to re-create my most favorite map of RA2, which was called "Official Tournament Map" Seen here.

While personally I think I made the map a bit too big; something I wouldn't mind redoing, as I had twice already, I think I was rather successful in reshaping it for a CnC3 map.
There's only one slightly kind of major issue with it, and that's pathfinding. I'm not sure if it's the bridges, the cliffs with the abundance of accessibility or something entirely else. And to be honest, I'd love to have some help with it seeing I haven't made a single map in forever, and tutorials are rather really hard to find nowadays.
Another small issue is that the bunkers on the cliff edges when garrisoned with infantry can't shoot down properly, which I find a bit weird.

The file is downloadable here: Dl.dropbox.com

There's also a few other smaller things I'd love to find out:
Like how to make the tiberium spots not look so horrible next to the snow.
How to make those sonic walls for the blue tib zones on the sides.
And if there's a way to make the textures not look so horribly painted on and make them fade out more.

Any help would be much appreciated.