well if there's anyone who's had issues with it, it's me.
firstly, no you don't need to uninstall old versions. i found it to work only after i deleted the old .esm for TTW. the 1.3a patcher is supposed to replace that, so after you run the installer.. try just setting the TTW install location to the same spot as FNV. it's just easier, plus if you go to options and check the boxes for not updating .bsa files and music files (the first 2 checkboxes) than it will go faster. when u click install and press 'enter' several times you might get a window that says something about an .ini file being unable to do something, just click 'Continue' and go back to the New Vegas folder where you deleted the old .esm and check that the ttw .esm is there, that means it worked since..u deleted one and have a new one..
than run the game and you should b ok. not all of what i said may be necessary but it's how i got mine to work. if u need a more step-by-step, just say so
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