fpp - isn't the OS 2006 kernel also used in OS 2007HE? So you only need to flash the rootfs from OS 2007HE to your device (see Fanoush's earlier post) and keep the kernel with high speed support.

Try tar'ing your OS 2006 partition that you have on your 512MB MMC (with compression) and see if you can copy the archive off to your new card where you can restore it. As for FAT, just copy it via a PC.