Require to have this validation as below:

Solution 

Step 1 – Tools > Customization Center.


Step 2 – Once Click Customization Center below screen will prompt > Double Click QnE Optimum.


Step 3 –   Expand Validation > Expand Rules


Step 4 – Look For QnEBS.BO.Sales.CashSales and QnEBS.BO.Sales.CashSalesDetails.

Note: Expand QnEBS.BO.Sales.CashSales.

 

 

Step 5 – Clone CASHSALES.DEBTOR.REQUIRED


Step 6 – Fill in as below. (To Control Cash Sales must be transfer from , but can transfer from any document)


If want to control Cash Sales compulsory Transfer from Delivery Order

Criteria Change as below: