After upgrading to Acubench 10.0, the colors in the Code Editor become corrupted after making modifications to your preferences and saving them.
Accessing the customization (Tools->Options->Code Editor->Format), the colors reported for "Keyword" or "String" don't match with the ones really used in the editor.
This is now fixed with ECN-WB945, released in next version 10.0.1.
You must remove your personal preferences file after reinstalling a new version of AcuBench.
This file is located in your personal APPDATA folder (for example, C:\Users\<yourname>\AppData\Roaming), in Micro Focus\AcuBench, and is named AcuCOBOL.ini.