Did you go for full outer housing for the rear derailleur or only inner cable?
For my rear and front derailleur, I run the outer housing from the shifters only to the frame. Inside the frame I used the plastic guide tubes the rest of the way. For the FD I would cut the plastic guide tube right before the FD to give the shift cable some weather protection and the TFSA frame should provide a rubber gasket for the FD hole. For the RD, I run the plastic guide tube all the way to RD hole and then I used the provided Shimano flex cable for the RD. You'll mostly likely have to cut it shorter if you're running a shadow style Shimano derailleur.
Also I would tape up your seat post and saddle rails. No amount of carbon paste will prevent slippage. I used non residual bar tape + carbon paste on the seat post inside the frame. If you're using a carbon saddle with oval rails, just use gaffer tape on the rails, it'll help keep everything in place.
