Panu, by connecting the parallel port you automatically get 2 of the 3 lines of the SPI bus! I am using 13 lines total: 8 for parallel port (which also includes SDO and SDI), SCK, XCS, XCSPAR, XWR, and RESET. I will look at adding the BLOCKMOVE0 pin to the shield. However, you don't need this pin to know when a block move has been completed. You could poll register 86h, checking the status of bit 0.
Microchip now owns Atmel, and thus has some better control over the MPE (which is the Microchip based Arduino). It will be possible to use the PIC32MZ version of the Arduino to decode and play MP4 files (video/audio) without needing any additional hardware. There are a lot of possibilities with the VLSI chip for sure.