There is very little aftermarket support for the Track/Kick ECU. Superchips in the UK list a chip for the 16V and a company in Greece ) list a chip for the 8V. There are a number of piggy back devices that can be used. A couple of people have used MS has also been used MS as a stand alone system or as a piggy back computer.
The 16V processor is not reprogrammable and it has no external programme memory. The processor is an Hitachi H8/538 clone.
I've been working on hacking the 8V ECU, the processor is a custom Mitsubishi chip (MH6211)apparently based on the 68HC11K processor, the processor architecture is not public domain. So far I have managed to disassemble the code and identify the fuel map (VE table). I used the instruction set for the MH6111 processor that is published on one of the DSM websites, although there appears to be a couple of extra instructions in the 6211.
I'm currently working on tracing through the circuit board to produce the schematics. Once that is done then I shall be spending some time with a logic analyser attempting to determine which block of code does what and where all the important data is.