I've only used the LCDK to validate my SPI code without actually talking to a SPI device. I vaguely remember I had HW conflicts that stopped me from using the SPI ports for testting. I checked the LCDK schematic and the SPI0 pins are connected to the Ethernet chip. Those same pins are NOT connected to J15 because resistors to J15 are not populated.
J15:SPIO_SIMO = SPI0_SIMO, Maybe remove R184, Add R214
J15:SPIO_SOMI = SPI0_SOMI, Maybe remove R179, Add R215
J15:SPIO_CLK = SPI0_CLK, Maybe remove R178, Add R216
J15:UART0_RX = SPI0_SCSN_4, Remove R173, Add R219
In theory, you can install R214-R219 and keep the other resistors. This will retain use of the Ethernet. See here:
http://e2e.ti.com/support/dsp/omap_applications_processors/f/42/t/234899.aspx