Downloading the games onto the Nintendo ds r4 card is not that complex as you think, below are the instructions:
1)Your r4 card should come with a mini SD card reader, that lets you insert a micro SD memory card into the reader and copy stuff onto the memory card. If you have it, insert the micro SD memory card into the card reader and insert the card reader into a spare usb port on your computer or laptop.
2)Then using Windows explorer, create a new folder called "GAMES" onto the root of the micro SD memory card, if it doesn't already exist.
3)Copy the games you want to load onto the r4 card, into the GAMES folder you just created.
4)Once you have copied the games, remove the micro SD memory card from the card reader and insert the memory card into the r4.
5)Insert the r4 card into your Nintendo ds console and power it on, your games will under the option called "Play Games" from the menu on the r4 card.