A better description is needed Max. What is your browser Chrome? Firefox? ... AI will not work with Explorer. Are you attempting WIFI or USB connection. To get help, you have to provide the basic information about your PC/device because otherwise, we can only speculate. AI2 works on MANY systems and the help is system dependent.
It appears you see the scanned code on Companion on the device. Is that true. If that is the case, the issue is probably a coding issue or an aia fle larger than 5Mb or more than 10 screens. Tell us about your project or is the first time you are trying to use App Inventor Max?
Regards,
Steve