Convert a Template to a Website

I would like to improve Shopify shipping function, it could be building into the exist platform or to be done as a additional app. Here is my requirements: 1. I need a filed to key in actual gross weight and choose package size for each order, and choose the heavier weight between actual gross weight and volume weight in order to calculate the freight cost. 2. Customer can only choose between DHL and International Air mail service, however, International air mail service have 2 different service which will only be visible to us for selection. 3. I need the system to calculate the actual freight cost automatically. 4. Two fields to entering order number and tracking number, both will be scan by bar code scanner. Follow by enter and to next order. 5. For the order will ship by DHL, I want the order sync to DHL easyship software automatically. (Attached with DHL easyship sample file) 6. Import all Tracking# back to Shopify directly and send out fulfillment e-mail then close the order. There's a shopify app calls shipstation, which can serve some request that I need, however, since I don’t base in US or Canada, I can’t use it. But you can refer to how it works. [login to view URL]