I just got the board and I am checking it out. I flashed the hex from the demo zip. UART, RTC and HID works, SD says that it was successful but there is no DIR1 directory or second file in SD.
I placed FILE_TOO_LONG_NAME_EXAMPLE_123.JPG in root directory in a fresh formatted 8Gb FAT32 Kingston SDHC class 4. I checked SPI and It looks like it works fine.
Should I tweak any setting in format options or its just incompatibility of compiled libraries and the specific SD card?
*Edit: I just managed to make it once. It made Dir1 and a 0Kb file. I have no idea how, just plugging and unplugging usb and pickit3, restarting etc. I tried to do it again but failed (removed generated files ofc)