SELO registration was updated in 2016 to an on-line process (see also online registration), since then registration is only possible via special software. All necessary documents must be digitized and uploaded. Even the mere installation of the software (.exe file) can lead to vast problems.
Once installed, the Chinese authorities have a very powerful tool at their disposal and the software itself is not necessarily considered to be “user-friendly”.
This is well known to us and we can offer appropriate IT solutions.