These are the conditions that have to be met for the batch to pop the window automatically.

 

1. You have to have the revenue type set to payment

2. There has to be a commitment to apply to

3. You need to have first entered an amount in the amount field

 

Once each of these conditions are met on the batch row, the window should appear for you.  You can choose to either default these or just enter them into the row, either way as long as they are populated, the batch should automatically open the apply to commitments window.