How to Set CUSTOM TOP to AR Lockbox CTL file instead of AR TOP?

Auto Lockbox is a service that commercial banks offer corporate customers to enable them to outsource their accounts receivable payment processing.
Auto Lockbox eliminates manual data entry by automatically processing receipts that are sent directly to your bank.
 
In order to load the bank files through Oracle Standard Lockbox Process, Oracle recommends only to keep the standard control file in $AR_TOP/12.0.0/bin folder, but when we have custom control files, oracle will not suggest to keep it in AR_TOP/12.0.0/bin folder, because when DBA's do any patch update all custom files will go off. We found an workaround solution where we can place custom control file in CUSTOM_TOP/12.0.0/bin

When we are passing a parameter value for Control file, if we give only control file name, program will search for given control file name directly in $AR_TOP/12.0.0/bin, so we need to divert to CUSTOM_TOP/12.0.0/bin with  "../../../XXPC/12.0.0/bin/Control_File_Name" as per below screenshot.