A retroreplay cartridge image is preinstalled in slot 1 (PAL) and slot 2 (NTSC), you can use that (press 1 or 2 in the menu). You can also install/load a jiffydos kernal and drive ROM if you like, but you have to provide the images yourself (see manual).
Tobias, could you give a quick sentence on where I shall put the jdos kernal and drive rom on the SD card and what to call them so that I can set my TC to enable loading of rom at boot ?