RE: Creating Cust Ledger Entries with the API
As rightly suggested by Mohana, no direct data entry should be done in Customer ledger entries, ask your Business Central developer to create a cash receipt journal page API for you and you can then enter data into this journal.
In Detail:
1. CLE (Customer ledger entry) is a table which records historical transaction data of all the transactions a customer/customers have. Including invoices, payments, refunds, etc. The data in this table is strictly used by Microsoft to further realize the GL value and link customers with Accounting
2. Since this table's purpose is to store "transactional logs", the only way to enter data here is by either posting invoices or processing journals. The video below will highlight some of the processes (on how those are done physically in BC) www.youtube.com/watch
3. Contact your BC developer and ask him to create an API type page of Cash Receipt Journal (if not already accessible OOTB by Web Services)
4. Later, all that's left to do is publish this page inside BC's Web Services: learn.microsoft.com/.../web-services