That config.ini is just a printer profile, not a driver for the mbot3d in repetier. Repetier writes the init config file to the Windows Registry under userkeys. You can use the config.ini to change those registry values but that can be tricky and isn't necessary. I am using Repetier/Slic3r on another machine and it had an older version, so I downloaded the newer version .95 and it wouldn't work, just the same as trying it before with the mbot3d. I think I have it figured out now. A printer profile can be set up in the printer settings panel, then named mbot3d so it will be written to the registry and will show as an option under the connect button. Main thing is make sure your mbot3d is being recognized as a comm port first, In the printer settings pick the default, then set baud to 250000, automatic, and click on the ping-pong box. Then hit connect. If the button turns green, then there is a serial connection but not communications. None of the manual control buttons will work. Hit the button again to disconnect. Then pull the usb plug from its port, then plug it back in again. Then hit connect again. It will seem the same as before, but now this time, click on the OK button down in the right corner. The printer heater temperature should show an ambient temperature value at this point, with a default heater value. The quickest way to check if the connection is good is just click on the manual jog buttons, +Z is a good start. I have not confirmed this yet with the mbot3d but it was acting the same, so this seems to be a couple small bugs in repetier that requires these steps. Skeinforge is an option for a slicer in repetier and it seems very crude compared to Slic3r. The workflow of repetier takes some getting used to but really starts to flow once you get the hang of it.