The sky3ds official will release the newest firmware to update the sky3ds plus and add more games. First of all, you need to update your sky3ds plus to the newest version. Normally, the r4is site will pre-updated the card for you, and you can disregard this step. To update the sky3ds card, you should format your micro sd card first. After done, download the newest sky3ds plus firmware v1.12. Unzip the firmware_v112-1, copy and paste the firmware.bin onto the root of your microsd card.
For more information and update about sky3ds plus, please check www.sky3ds.com