I have a couple of problems recording COGS in Zoho books:

The first one: 

When I want to purchase an item I create a Purchase Order and I include the purchase rate of this item, the rate is the cost of the item and is included as an inventory asset. When a sales is made, the inventory asset is reduced and and COGS is increased by the same amount. Until now everything is OK. But I want to record freight-in charges, custom duties and clearance as part of the inventory asset when I receive the item, and when the sale is made, it should all be transferred to the COGS, how to do this correctly? What I did is, I created separate COGS accounts for freight-in charges, custom duties and clearance but these appear in P&L statement even before a sale is made so it does not calculate COGS correctly and it is not included in the inventory asset in the balance sheet, as I think it should be? I want all freight-in charges, custom duties and clearance to be recorded as inventory asset and when a sales is made it gets all transferred to COGS including the purchase rate of an item. 

The second one:

As I am new to ZOHO Books and my current software does not allow me to export my items, so I have to input all of my items manually. I input the item name and the sale rate along with my purchase rate in order to record to cost of goods sold of that item. But I when I make inventory adjustment to reflect the quantity that I have in hand, I have to record the adjustments in a COGS account, not in an inventory account. So once I do this, My Profit and Loss statement shows the COGS even before any sales occur. So how to fix this or, in other words how to do it properly in my case?

I am not an accountant or an accounting expert but I like ZOHO books and trying my best to run my business correctly, thank you for your help!