Referring to files in the initial RAM disk

[NiKiZe]

use imgstat to see what you have loaded.
But AFAIK there is no support for loading additional files into ipxe via the "initrd" interface.
If there is data there, it will be parsed as a script and nothing else.

What you might be able to do tho is to embed this into original ipxe build (in which case multiple embeds are supported)
But not sure if it in that case is possible to override the script. You might also have to include both a script and the image, otherwise the script that you send via initrd might "overwrite" the image rather than just adding the script, but this is something that you will have to test, if working at all.