It appears that whatever you are trying to burn into NAND flash simply does not fit.
Try using LoLo's
info command to view the amount of memory on the board. Then take a look at the size of the file you are trying to put in there.
Also, you ought to be using YAFFS (or some other file system) to burn something into NAND. In general, anytime you use NAND flash you want to go through an appropriate flash file system that can handle bad-block management, errors, etc.
Check the LogicLoader's User Manual for information on using YAFFS. In general, you:
*losh> add-yaffs
*losh> mount yaffs
*losh> cp whatever file you want into YAFFS (try TFTP for this)
* access the file however you like using the normal LoLo file commands
Regards,
--mikee