These are the plain files from my VTech Dx3 Watch + The latest firmware and OS .bin file and the CPU and instruction manuals
The watch runs FreeRTOS and its executable format is .kpa and jpeg is the image format. AVI with the mjpeg codec is the video format.
For now really all you can do is copy these over to another dx3 or dx2, dx, or dx4. An extracted copy of VT System is in an encrypted partition. But you could run this in qemu somehow. You can extract the .bin with binwalk
Use these for if you want to jailbreak it I guess but the learning lodge app does use a script to load the .bin so remember that
You if were to jailbreak this you want have to update the firmware via the app then when it tells you to disconnect just reconnect and swap the original firmware with a modified one.