reading usb memory with vdrive2

hello i am trying to find information how to use a vdrive2 usb memory adapter with arduino. the task is to read a data file from a usb disk on key memory into an arry in the arduino mega. the data file is a file with several numbers in a CSV format, comma delimited . i looked around but failed to find a straight forward answer. i would like an example code to start from so that i can work from it to build my own project thank you ran