http://www.r4isdhc.com/ is the official site (or that is what I could make out from the photo on the store you linked) store links however are not allowed here
Take it you got the official 3.7b kernal
You should just be able to extract the roms directly on the MicroSD
A game should be shown on the 2DS to represent the flash card (this is just with the kernal on the card) [If nothing is shown then it has not worked and it is possible that the firmware on the 2DS is too high for the card to work]
once you load the card a menu should show, even if the nds files are in the incorrect location then you should be able to look through the folders on the Micro SD from the menu
I don't have this card myself by the way I use a few kits but not the R4 clone series, the only R4 I ever owned was the original one that even back then was a clone of a M3 card from back in the day
I'm not even sure you have a real kit or just fake version that will not work with the official r4isdhc kernals