Transfer Payment for Project Cash Management-CJFN

Hi Experts,

We don't have the Funds Managemet module inscope, but PS with PS cash management in the scope to monitor the project specific cash flows (in & out payment flows).

I have received the advance payment  When I invoice, then i can clear the invoice with the already received downpayment.

In this scenario, should I run "Enter Transfer Payment-FMWA?", if not where do we use it?   or

should i run the transaction  "Transfer Payment for Project Cash Management-CJFN?" , if so, what is the significance of this transaction.

Thanks,

SAP99