TX internal storage is a NAND flash chip. This is difficult for a few reasons, mostly, because NAND needs wear-leveling, and special filesystems, neither of which is standardized. There isn't even a standard way to lay out a partition table! Thus to get TX internal storage to work there are three components to be created: BlockDevice driver to talk to the NAND chip, PartitionManager plugin to figure out the partitions on the device, and filesystem driver for the FS used in the TX (something called "BFFS").
I am happy to report that the first two pats are complete and working. The third is harder, however I've had some help from a programmer in China (irc handle tech_junkie_chz_5481), who seems to know a lot about this BFFS and has helped me craft a driver for it all in one night. The testing is going to start soon.
PS: Hello from Buenos Aires!