Hello,
Thanks for the detailed description of the problem. It does sound somewhat surprising, since you say that the IPN message was successful.
Balances are not affected because the deposit transactions are not recorded. I assume this is a new installation since there are no transactions in the list. The question is, why would transactions not be recorded if the IPN message was sent successfully?
1. Please double check that the deposit address that you are sending funds to is the same as that shown in the plugin. You can check deposit addresses via Wallets -> Deposit addresses, or in the user profile screen for each user.
2. Enable the WordPress debug log, and resend one of the IPNs from CoinPayments. Do you see any error in wp-contents/debug.log? What about the PHP error log, or MySQL error log?
3. Is the status of the IPN message 100? If not, this is an early IPN message where the transaction is not yet confirmed, and there will be a subsequent IPN message with status 100. Only these IPN messages (with status>=100) are used by the plugin.
I really cannot think of anything else at this time. If the deposit address is correct and the IPN is successful, the deposit should be recorded, or if something unexpected happens, there should be some trace of the error in one of the logs. There is no other outcome that I can think of.
So please check all of the above and let me know.