How to use this library

Hello,
I am using this library https://github.com/grintor/QRprint to print QR codes using Arduino. If you check the values in frame.c (https://github.com/grintor/QRprint/blob/master/QRprint/frame.c), and in qrprint.cpp (https://github.com/grintor/QRprint/blob/master/QRprint/qrprint.cpp), it should be clear that the string to be printed as a QR is truncated (hardcoded) to 47 characters. I tried increasing this number and replaced my frame.c file with your version71.c file but the printer generated odd QR codes that are neither scannable nor compliant to the QR figures standards. If you could please guide me through the correct process to generate version 7 QR codes or higher I would really appreciate this since it is very critical to my project. Thanks a lot