Sorry, your device is not currently supported by emCORE.
Porting emCORE to a new device is generally a lot of work and requires lots of experience with embedded system development.
The exact amount of work needed varies greatly and depends on the complexity of the device and similarities to devices that emCORE has already been ported to.
Your device is vaguely similar to other devices that emCORE supports, and emCORE can already be booted on it from a RAMDISK, but a significant amount of work remains before it can be permanently installed and access the device's flash memory. Until this work is done, the emCORE port to this device isn't of much use.
Running emCORE from the RAM
As of now the only way to execute code on the Nano 4G is through the Notes vulnerability and with Pwnage 2.0. As we don't know yet how to initialize the SDRAM on the Nano 4G the only useful method is by using the Notes vulnerability. The only working note at the moment is an iBugger loader.
Simply put the "n4g-ibugger.bootnote" in the "Notes" directory of your Nano 4G and safely remove it. A Mandelbrot set should be displayed on the screen with some text stating it is Unified iBugger loader v0.1.1 running on Nano 4G.
You can get a recent emCORE build for your device from the builds page.
To run emCORE, enter these commands:
python ibugger.py upload 08000000 emcore-ipodnano4g-rXYZ.bin python ibugger.py execute 08000000 0a000000