Some quick notes. It is possible to choose either "build-in menu" (which is neoflash 1.03), no menu at all or a custom menu. The custom menu can be of any size/form/whatever as long as it supports the neoflash menu type of storing the flash rom infos. Currently, the PCE/TG16 selection is hardwired to PCE.
For those who are interested, here is a commented disassembly of the neoflash menu 1.04: http://deadcoderssociety.net/pce/bio...isassembly.txt
It might have some misinformation.. whatever. I did not really pay attention to things that are not essential to get the flash cart rom switching to work.