I\'ve been polishing up my original 5500 dualboot scripts, and have a couple things that might help.
First, I\'m setting it up to properly handle if /sbin/init is a program or a symlink to telinit. Also, instead of using the mtdram test driver to read a jffs2 initrd.bin image, I\'m switching to blkmtd, which is a test mtd driver you can point to a block devices (such as a loopback device pointing to the initrd.bin file). This should help in being able to convert a larger image file (i.e., no more out of memory errors).
Finally, I\'m going to try and do a pdax2sd for the sl5500. The main differences between this and the standard oz2sd is that oz uses a single file system, which is read-write. The standard roms for other sharp models (5600 & above) have the flash divided into multiple partitions, with root being read-only and the user area (/home) read-write. I\'m not sure what the pdaxrom uses, as I haven\'t looked at it that close yet, but if it\'s the same structure then there will be startup scripts along those lines to be modified accordingly.
My new 5500 dualboot stuff will be posted shortly, and I\'ll try my hand at working with the c-series rom images to see what I can do (of course, won\'t be able to test myself as I don\'t yet have one of those models).
I\'ll keep you posted on the progress.