Download the FO3 & FNV version of your choice. Copy both to an empty folder. Extract the FO3 files first, then extract the FNV files and overwrite when asked. Ignore the esps for the moment. Use the version of BSAOpt that came with your TTW installer (Resources folder) to pack the meshes and textures up - make sure you select 'No Compression'. Drop the esps in your data folder. Make sure the NV version loads before the FO3 version, then open edit. Load only TTW.esm and the two Vurt's plugins. For Vurt's NV - Add Masters (all of TTW's files,) Sort Masters, trip the ESM flag. For Vurt's FO3 - Add Masters and Sort Masters(all of TTW's files). Save and close Edit. Change VFO NV's file extension to .esm. Reopen in Edit, run the TTW conversion script, then add VFO NV as a master and all of FO3's records into it.