I worry about this, but I have a guinea pig...  he wants a "new tune" that is "cutting edge".
Frankly I'm excited by this project.  I guess we'd have to compare the modules for knock recognition and the intake setup, but we'd run into problems if the modelling dimension of "parameter-space" grew too large.  The FR has enough explicit detail if the board's commentaries are joined with the FR.  In fact, that's a OT-thread unto itself:  "pages in the FR which have threads associated", which could be quite useful.

Totally agree with you on the impact of RS-altered hardware not present on the S-model... can this be fixed?

You are definately right that it will work somehow but it also depends on how the car is used. If you use it only as a drag car on a sunny day you won't be bothered as much by some cut corners as you will use it as a DD in winter.

I have no first hand experience with a RS4 file on a S4 but from my general calibration experience I'd say that the main topic will be the intake model as you have a different throttle body and intake manifold. This will influence cold start, idle speed control and dynamic fueling behaviour mostly. So taking over the S4 values in that deparment will most probably help. Unfortunaltely this can't be done that easily in some cases as the RS4 uses an other structure for throttle angle precontrol in the start phase for example. Also taking over the knock recognition stuff can't hurt if you are on stock engine hardware as the noise behaviour of the RS4 engine with different pistons and cams should not perfectly fit the S4.

Maybe I'm just a bit hypersensitive on stuff like this because of my working background and all of this is no problem and works fine for most needs, but I wanted to make aware of it.     

thanks for the heads!  In reality many of us with the serious builds are running the rs4 intake pieces and or heads so it should greatly improve those same areas.  I have attempted to make changes for it yet still to this day i do not know if they worked.

What makes you thinks it is pedal related? Did it shut off when you did a tip in or just like that?
Using a bigger throttle body with a S4 file is not that big of a deal because the start and afterstart phase is calibrated with the small throttle body so worst that can happen is your rpm overshoot is too high. The other way round it's not that easy.

Try it with KLAF copied from a S4 file or better all variables of BGMSZS.
If this doesn't help you have to log the start with the varibles I have told you plus wdksom_w

Ok,
only 1 real DTC is not bad for the first try.

DTC 16984 - P0600 means "Datenbus Antrieb fehlende Botschaft" => "CAN data bus malfunction / CAN message missing / CAN time out"

I believe that`s a problem with an expected CAN devices which is not there.

Can it be that you have no ASR/ESP in your car?

The "7" in the ECU coding of the 551K (coding 10711) and the 551Q (coding 5711), means that the car has ASR/ESP over CAN bus.

So it can be a coding failure.

ASR/ESP is a critical device.
If there is any failure, the ECU runs in limp mode and the car has no power.

Does your car have ESP?

No, car does not have ESP.  My car is currently coded to 06611.  I'll reflash and then read the code that is on there.