My control panel just switched to English after closing it down the first time.
This isn't a huge help, but a screenshot of mine with the English attached. Highlighted bits of interest. Green bits - refresh list of printers. Once found, select your printer and press the link button (assuming it doesn't automatically link - check the status of the printer)
Purple area - drag your gcode in here to copy it across. To start a print, select it in the list of files and press the button highlighted in cyan.
Hopefully, this gives you enough to check you can copy files to the printer and fingers crossed yours switches language soon.