When I try to do 

resp = zoho.crm.getRelatedRecords("custommodule3", "Leads", "1280922000001794916", 1, 3);

I get

{"4401":"Unable to populate data, please check if mandatory value is entered correctly."}

When I try

resp = zoho.crm.getRecordById("custommodule3", 1280922000001794916);

I get the expected Map with data for that record in the custommodule3

Now please pay attention to the first integration task in Zoho Creator, is of type String, whilst the second is of type Integer, why this discrepancy??

The above task only works with Contacts in Accounts, although the script builder enlists  custommodule3, it seems that is not valid at the end.

Please revise and help as we need to implement this to track multiple Lead Contacts and integrate with a Zoho  Creator App.

Thanks

Manny