Arekeneras

Hi, I'm obviously new to Nexus and I'm probably doing something wrong, but I just can't download any mods. I have the Mod Manager open, and I'm trying to install SkyUI. I click the "Download NMM" button, and it gives me a popup saying I need the Skyrim Script Extender. I downloaded that, but it still isn't showing up in the manager itself. What do I do?