Raúl Luna asked me to participate in the project, as noted, joined the team; he has a lot more experience than me in modems. He immediately offered to help me fix the GSM module I created.
I redesigned the GSM module with his advice, while Raúl (Despite the tight deadlines of his project) took a few moments to create a more updated version of the GSM module.
Also I have been quite busy and I have not had the chance to continue the project.
Next step is to update the various boards and preparing a new panel to be implemented hoping not to find other mistakes!