vervurax

NifSkope 2.0 dev4 can read from ba2 and loose files, you can set it up to show all your textures from base game and mods. The order of folders matters, though so this could be a problem. I can show you my setup in a few hours if your interested.

NifSkope is an option, but it will not look the same as in game. Steam is not the only option to take screenshots, your best bet is to install Fraps, MSI Afterburner or whatever program that's capable of taking screenshots. Set whatever hotkey you like and problem solved. Screenshots will go directly to a folder you specify. Method 3 of 4 here http://www.wikihow.com/Use-Fraps-to-Take-a-Screen-Capture shows how to set up screenshots, you can disable FPS counter and recording if you don't need that.

In response to post #30547605. NMM works fine, the problem is that some mod authors don't care or don't know that they should pack the mods with proper path files. I just fixed two mods, zipped them, installed them manually in NMM and the textures showed up.