I'm wondering if this is anything related to some of the clever stuff that's being tried out with PDAXROM that modifies the partitioning scheme (single root partitions etc.)... not sure how much has been implemented - have been watching interestedly from a distance on this one.
I would suggest that you use a NAND restore to get back to the original Sharp ROM.
By the way you need a 256Mb memory card for this, the image is just over 128Mb.
Once back to the Sharp ROM I would give Cacko another go though - if you want an English ROM then it's much more useable than the Sharp ROM
This link is from the HOWTO pages and has downloadable NAND images...
http://downloads.conics.net/pda/zaurus-sl-c700/service-menus