I've only just discovered this gem TTW (after many years absence from the series) and what a brilliant title if FO4 is to be added as then you only need change two to three ;)
Anyhoo, I am here to offer my admiration to the developers (and respect to their families) for bringing these 2 great games together as one. My experience thus far went as follows ...
I installed with NMM which froze at the end of installation and remains in a grayed state with the only option to disable as there is no green tick. Yet, all files installed perfectly (I checked each file against the created fomods contents) and the game loaded w/o problems.
It was s wonderful to experience FO3 initial starting quest and I sat through the whole intro before beginning in vault 101. I experienced freeze screen while attempting to exit the vault however, upon loading the most recent save file, I exited to the magnificent view of Megaton and to enjoy a new experience with the almalgamtion of of two great titles.
Game is still running and I just jumped out to let you guys know you made an old fart very happy, Thank you:)
