Okay, so this has nothing to do with Combat Robots: I pre-ordered a 32GB Microsoft Surface with Windows RT a couple of weeks ago, and it showed up (on time) last Friday. Since then I've been playing with it, and one of the first things I noticed was that less than 20GB of the 32GB SSD was available for data. Luckily, though, I had ordered a 64GB microSD card from Amazon earlier last week, when they had them on sale as the Gold Box deal of the day. I received it Monday, and put it in. Then I was scratching my head trying to figure out how to actually use the card to store stuff. Windows Libraries don't let you add removeable media as a Library source location. I tried mounting the card as a folder on the C: drive, and that didn't work either. Finally I got it [almost*] working, and figured I'd post the steps I took for posterity. Click Back after viewing an image.
Make an empty folder on the C: drive. Note that I've called it SD2 as I still had the SD card mounted as C:\SD from my original efforts. On my SD card I have already made folders for Documents, Music, Pictures, and Videos.
We're going to make symbolic links within C:\SD2 to each of the folders; specifically we're going to make Directory Junction points - I tried hard links and directory symbolic links, and they didn't work. Use an Administrator command prompt to run these lines:
mklink /j c:\sd2\d d:\documents
mklink /j c:\sd2\m d:\music
mklink /j c:\sd2\p d:\pictures
mklink /j c:\sd2\v d:\videos
Having run the above commands, check that you have four directories under C:\SD2.
Open Control Panel, and select Indexing Options. Choose Modify, and check C:\SD2 as an indexed location. Hit OK and Close, and exit Control Panel.
In File Explorer, click the Documents Library, and on the ribbon click Properties. Click Add, and select the C:\SD2\d folder. I set mine as the default Save Location so any new documents will be saved to the SD card by default. Repeat this process with the other libraries, adding C:\CD2\m to Music, C:\SD2\p to Pictures, and finally C:\SD2\v to Videos.
Next step - verify that it worked! Open XBox Videos from the Start screen, and go to My Videos - you should see whatever content is in D:\videos displayed.
Do the same thing with XBox Music - go to My Music, and you should see the content of the Music folder on the SD card.
Finally, open Pictures from the Start screen, and go in to Pictures Library.
Ta-daa! The contents of D:\Pictures show up! Now, about that asterisk from above: you'll note that there is no content in the Camera Roll folder. I did actually have a couple of pictures in there, but they don't show up, even when you go into the folder. If you have a video clip you took with the camera in that folder, it does show up, which is weird. Note too, that I renamed an automatically-created Camera Roll folder to Camera Roll2 and it shows up fine. Curiouser and curioser.
Still, it's 95% functional, so I'll go with it. Hope this helps other people trying to see SD card content in XBox Video, XBox Music, and Pictures!