I forgot to mention that process in the video so here we go...
I'm not sure why Rakuten got rid of the Global Rakuten storefront. Perhaps it wasn't popular enough to maintain when AmazonJapan became increasingly convenient for overseas shoppers.
With Global Rakuten gone, unfotunately there isn't a central website with a platform for an English language storefront. So, the only way to shop from Rakuten Japan is through the same page Japanese shoppers would use. That leaves international shoppers that don't have any understanding of the Japanese language out in the cold. My only advise then is to use a web browser like Google Chrome and enable automatic translation of the Japanese web pages (its far from perfect, but it does lessen the confusion).
The Global Rakuten Express aka RGX is basically an international shipping service. Once you register with RGX, you'll receive your own address (like a PO Box). The address is unique to you, and is your hub for receiving goods you purchase online. You also have the ability to purchase stuff not only from Rakuten, but also from places like Yahoo Auction, Ebay Japan, Amazon Japan, etc.
You asked why my purchases from two stores, i-Tools and Ehime Machine came in one single box to me. Let me explain:
I purchased from i-Tools like usual and had it sent to my unique address issued by RGX. I did the same with my order with Ehime Machine. Two separate orders, but with the same shipping address.
Once the items are received at the RGX shipping center in Japan, you'll get notifications and you can verify it through your online account's 'My Page'.
I then selected an option to have them combine the two boxes for final shipment, to my home address.
They will re-pack your stuff neatly and provide you with a shipping fee quote.
You pay off the shipping fee and within a day or so, you'll get an email with a tracking number. By that time, it's likely already on the plane.