Usually, in case if someone has his/her own customized checks and want those checks to be printed, on generation of payment, and at the same time want to block printing of standard AX Checks all what needed to do is following.
Proceed to following path
AOT\\Classes\VendOutPaym_Cheque\printDocument
Find below line of code which will be most probably at end of the method
bankChequePrint.printDocument();
The line of code is responsible for cheque printing. You need to comment this line of code and put your own logic to print your customized document/ cheque.
Note: There is possibility of customization of existing checks, but those give you more hard time, than creating your own. Its up you, how you want to proceed, either by modifying existing checks or creating your own
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