WebDriverException: Message: unknown error: unrecognized Chrome version: HeadlessChrome RobotFramework
Upgrade the chromedriver to the latest - currently v2.30; this issue should be fixed in v2.29 (and yours is older).
Also, according to the doc you need to uncomment the remote_debugging_port argument.
Btw, unrelated, the variable is called ${options}, but you are passing in desired_capabilities ${preferences} - a copy and paste error?