Hi,
For perform a NAND write/read you could use the boot loader which Freescale provide with the i.mx25(u-boot or redboot)
The instructions are here for redboot:
Flash memory (CM-i.MX27) - BlueWiki
If you want to check and verify the R/W signals you need to solder cables in the pads and perform a R/W then check with a logic analyzer and compare against the signals in the data-sheet of the NAND manufacturer.
Regards,
-Israel.