I have the full version of the Wkipedia including all sub projects eg Quotes, Dictionary etc. on a 16GB SD card. On using the auto download software I experienced a fail after downloading for several hours. The message advised me my card was full and to obtain a 16GB card. All of this was of little use to me obviously.
If the following isn't already inbulit and I was just unlucky I'd suggest the addition of a precheck of space available as against the size of the data to be sent with an advice to the user that insufficient space is available. Far better than a fail after much time wasting and useless downloading has been experienced.
Perhaps then a warning that files will need to be deleted by the program to make space and/or a request for an alternate download location would be a good solution.