Hi TeeCee,
The installer does not just add things to your system. It also copies proprietary models from some of your existing folders to some of the new folders that it installs. The errors are saying that before you ever ran the installer, you are missing certain .mdl files that it wants to copy. It looks to me like the missing .mdl files are all from Tongass Fjords FSX (TFX) folders that should be in your Boats folders after you installed TFX.
Go to your P3D\SimObjects\Boats folder and see if you have these folders:
AI_Vessel_TF_Volendam_FSX
AI_Vessel_TF_USCG_Anacapa_FSX
AI_Vessel_TF_Princess_FSX
AI_Vessel_TF_Fishing_Boat_FSX
AI_Vessel_TF_Matanuska_FSX
Those folders should contain the models that the installer is looking for. If you don't have those folders, then your TFX installation is not correct. If you do have them, then inside each of those folders will be a folder named "model" or at least starts with the word model. Inside each of the model folders should be a file named xxxxx.mdl. Let me know if you have the folders. If you do, then let me know what .mdl file is in each one of those model.... folders.
Rod