Hello @MTal
upon closer look I don't see how waiting while Check network registration < 6 would make any sense. The command, I guess that it issues, is: AT+CREG which would yield something like: +CREG: 0, 1 if connected to the home network or +CREG: 0, 5 in case of roaming.
You could add a print of the result code of check network registration to see the value you get. If it's 1 or 5 then the modem is registered to the network and you could change the code accordingly.
BTW: Interestingly on the product page there is a Chinese version of the UIFlow code which omits the registration check. (I wonder why.)
Thanks
Felix