The HunterLab Quick Start sheet that is included in the front of your User's Guide can be downloaded here. For the ColorFlex Citrus, go here.
ColorFlex User's Guide Chapter 2, "Introduction to Your ColorFlex System," which includes a description of the instrument, its accessories, and its options, as well as an overview of its button commands and installation instructions, can be downloaded here. For the ColorFlex Citrus, go here. For the ColorFlex Tomato, go here.
If additional assistance is required, you may contact HunterLab.