ADDING an ACM to an existing Trip is no different to adding a "New Sector"
First select the Trip which needs to have the ACM added to it then select the New Sector option

Then enter the New Sector details - then select the Net Remit Field and Enter the Net Value as a NEGATIVE Value the commission will automatically return a POSITIVE result next select "Create Sector"

finally select Create Sector and the details will display like the following
