Zen Cart v1.58a
Paypal RESTful v1.0.2
Payment Action: Auth Only

I disable PayPal Express Checkout and enable Paypal RESTful today.

There are two orders. The 1st order is paid by PayPal Wallet, and the 2nd order is paid by Credit Card.

The 1st payment goes through, but the 2nd order gives me an error:
The payment module's observer (auto.paypalrestful.php) was not loaded; the payment module has been disabled. The payment module has been automatically disabled.
Both orders get this error when I capture the payments, but I can get correct $$ into my PayPal account:
Request URI: /ipn_main_handler.php, IP address: 173.0.81.140, Language id 1
--> PHP Warning: Use of undefined constant MODULE_PAYMENT_PAYPAL_ORDER_STATUS_ID - assumed 'MODULE_PAYMENT_PAYPAL_ORDER_STATUS_ID' (this will throw an Error in a future version of PHP) in /zencart/ipn_main_handler.php on line 475.

Something under PayPal Transactions doesn't look right.

Attachment 20651

Should I remove PayPal Express Checkout completely? Or any possible issue I missed?