Memory Card Plus restore utility I made few days ago is now obsolete : I added a menu to select the firmware to flash.
Firmware list includes Action Replay Plus/Pro (various versions), latest Pseudo Saturn, Memory Card Plus, USB dev cart.
Firmware selection menu
As you can see, I added some colors in text display too 
The utility doesn't read data from the CDROM, so that it can be uploaded to Saturn via commlinks port (Action Replay) or USB port (USB dev cart).
All the firmwares don't fit as-is in Saturn HRAM (1MB), so I compressed them by using LZF compression, so that everything could fit in a single ~800 KB binary file
Here are some pictures of utility running on real hardware :
Firmware selection menu from early beta version.
Picture provided by r1cola.
(
click to open video)
Flasher in action : from firmware selection to end of flash operation.
Video provided by zorlon.
You can download this utility here :
flasher_20140824.7z →
flasher_20140902.7z →
flasher_arp_20150326.7z →
http://ppcenter.webou.net/pskai/ 
Disclaimer : You will loose your cartridge backup data after reflash. And, I'm not responsible in the case I brick your cartridge and/or damage your Saturn.
Read more Saturn cartridge firmware flash utility : small update
First, let's introduce to you memory card plus :
Black cartridge : Memory Card Plus
White cartridge : official memory card
Memory Card Plus looks like regular backup cartridge, but behaves differently : while regular backup cartridge provides memory on CS1 memory area, Memory Cart Plus have flash ROM chip mapped on CS0 memory area, as Action Replay does.
Consequently, Memory Card Plus boot before game on CDROM, and during this this time, it modifies some settings in order to make BIOS detecting this cartridge as a second backup memory device.
As Action Replay cartridges, it is possible to reflash Memory Card Plus, and in the case you would like to restore its firmware to its original state, I prepared a flasher utility containing my Memory Card Plus firmware I dumped 2 years ago (time flies ...).
You can download this utility >here<
(source code is included, please refer to readme.txt for installation instructions)
Flasher tool in action ... well reflash don't work under
yabause,
but should work on real hardware.
As en extra, I let my old game saves with firmware itself ... please format cartridge from BIOS memory manager if you don't need them.
Good old times I played Night Xmas and Shining Force 3
Remark 1 :
Flashing your Saturn cartridge will erase all the data on it, including your game backup data,
so use only after saving backup data to Saturn internal memory.
Remark 2 :
Memory Card Plus firmware is designed to work only with specific flash chips, so it
probably won't function correctly on other cartridge (Action Replay, USB dev cart, etc).
Disclaimer :
I'm not responsible of damages that this utility may cause to your game save data, Saturn cartridge or Saturn itself.
Please let me know if reflash worked (or not worked) in this article comments
Extra : I also made a diagnostic utility that displays flash chips ID without modifying flash memory contents. It can be downloaded here.
It can be useful when analyzing exotic cartridge, but not really useful with Memory Card Plus.
Read more Firmware restore utility for Saturn Memory Card Plus cartridge
In this article, I will explain how to build Saturn cartridge firmware from Saturn executable file.
Note
: it doesn't magically convert .iso files to cartridge format ! It only
convert standalone executable (typically, a file that can be executed
after being uploaded to 06004000 address), and doesn't support programs
that use CDROM.
So, basically commercial games can't be converted, and only some (not all) homebrew programs can be converted.
Read more Howto : Build Saturn cartridge firmware from regular Saturn executable
