Thanks a lot for your patience shabaz, I have checked all your points yet again.
I can only measure my load with a multimeter, yielding 51 Ohm. My multimeter isn't the best, then again, the load might be that one ohm off. I don't assume it makes that much of a difference (practically 2%) if to be used at low frequencies in the future. Made out of 2x 100Ohm 0805 resistors with the film pointing up to reduce capacitance at the cost of higher background noise sensitivity. The goal was more to verify I can get the instrument to run at all. I don't suspect any wrongdoing from it, but please correct me if am wrong.
As you can see in the second picture above, I tried calibrating for 100 kHz - 30 MHz, with the top left blue "Cor" confirming a 1-pt load calibration has been performed by following the 3 steps closely. First open, then short, then load. I checked and pointed on them to be absolutely certain, to no avail.
I am only using SMA and I am very cautious when shopping for them in person. I can confirm, I only use SMA. Lastly, I verified that the N-connector to SMA has no defect. I can measure continuity on its line, it is brand new after all.
Again, I have never ever seen just a dot or a line since crossflashing, even after factory resetting multiple times. I admit, my linux-and-cmd skills are non-present and I closely followed the tutorial, sometimes with the help of ChatGPT to elaborate on a step (putting the entire outline + descrp. into the prompt), so I cannot cross out my incompetence. Then again, the device otherwise works as expected, showing the VNA mode under Modes and the SVA Firmware in the System Info. If I messed up the files, please let me know what I could have missed. I am willing to screenshare my telnet if someone is intrigued to have a look.
Thank you so much! Again, this is my first experience ever with a SA /SVA...