Hello, I'm now copying in the function returned by MakeFunction when a==1 into relax. I have noticed that this has the ability to handle miscalibrated pulses via the R180_3Dx() function, however the pi-pulse angle is 180 + a degrees, where a is hardcoded to 0.0 degrees. Is this a planned future feature? It is also not clear how the R1 relaxation rates for states G and E (or A and B) are used. Is the aim to have R1G (per spin), R1E (per spin), and the pulse angle (all per magnetic field strength) as optimisable parameters of the model? For the current implementation, I will just set these all to hardcoded values of zero, as neither relax nor the fitting_main_kex.py script appear to use these. Cheers, Edward