I had one heck of a time installing TFX in P3D V4 also. I was finally able to get it to work. The only issue I have now is Sitka and Wrangell crashing and I suspect it is due to a few corrupt AI files I read about once but can not find at the moment. The next issue is the convoluted RTMM files. I did this foray once already and it resulted in a complete wipe and reinstall of P3D V4 because of crashes and errors. Again, I suspect traffic files but I am not sure. P3D is the future so I would hope someone somewhere will make a proper installer for all. Sure would be nice to just buy RTMM, install and be done. In the mean time I have been flying AKA instead until I can figure this out. I put Tongass at the top of my library to get it to work with my global, vector, NA LC, and regional sceneries. I backed up all of the folders I added to just in case I had problems again. What exactly happened with your install? Did you follow Poppets guide?