Seat Retrofit -- New Module is throwing codes

[dalbreez]

My pleasure, 
If you have not touched, replaced or added TRM and IMS. They should not appear in the HW changes avoiding to perform total upgrade. 
If your car is equipped with IMS (internal motion sensor), you should see a button on the center screen "reduced..." which disables the motion sensor (IMS). In the VIDA, you should see "Remove IMS" under the functional changes on demand.  None of the items in the functional change blocks a total upgrade. 

Same thing with the TRM. (Towing module). If you have not added or replace this module it should not appear in the HW changes. 

However, I don't know if you buy the second hand or brand new, if it's second hand and if the previous owner retrofitted those modules it's a different story. 

Regarding the seat controllers,
There are two different risks here. 
1) If VIDA would reload them or not.  You won't be able to know for certain until you actually purchase the reload software and try to install.   
    Yes, in theory; if the part number is listed as replacement part number for your car, it should install.  Worse case, you purchase the reload for one side first $90 USD and      try to install. If it does not install "This part does not fit your car", you can request a refund. 

2) VIDA reloads the module (seat controller) but you might lose the seat extension functionality.
     In this case, you can purchase Orbit and re-enable the seat extension and other nice stuff. But the downside is, you will need to revert those config changes (example:         seat extension) before visiting the dealer or connecting the car to VIDA.

Thanks so much -- I am quite convinced that the dealership just mentioned TRM and IMS because they are other modules and they wanted to 'make sure' nothing was changed -- the car was updated multiple times under my ownership before the seat swaps (with no issues), and so I think we can just carry on and assume that the only retrofit is indeed the seat module swaps. 

Sounds good. So, in short I should get VIDA with the adapter and a Windows computer, and specifically am I downloading just the PSMR and PSMD reloads for the seat modules? I can ignore IMS and TRM entirely. 

From there, the three possibilities seem straight forward: 1) it works! 2) loading software works, leg extension no longer works; 3) loading software doesn't work. 

If I had the original seat modules maybe I could just swap them in, and no need to install anything? But just risk the functions dont work?