Hi,
You need to sit with a logistic consultant for developing this report. Since this is a customized report, only inhouse consultants will be able to help you out.
This report consists of many parts :
i) Relationship between GL and movement type - You need to understand MM-FI integration. How based on valuation class and movement type, GL's are assigned based on transaction key in transaction OBYC & OMWB. Here you need to consider only those movement types related to returns. Also, have a look at tcode MB5L.
ii) Goods in transit - Check the logic in Tcode MB5T. Based on EKBE table & EKET table, you can find out how many goods are in transit. It is basically the difference between quantity of goods issued - quantity of goods delivered.
No idea what BOH is. Is it stock on hand.
Regards,
DPM