Hi Gresis,
Apologize for the delay response.
We have analyzed and we have prepared simple sample based on your requirement. Please find he sample in the below link,
In the given sample, we have mapped the properties of CustomData in the ViewModeland added an Appointment in the Schedule. By creating instance of CustomData you can create appointment, In the Schedule page you add your appointmentCollection from the SharePoint.
If the given sample doesn’t meet your requirement could you please revert us by modifying the provided sample, it will be helpful for us to analyze on it and provide you a solution.
Regards,
Subburaj Pandian V