I have used all the available resources to look for this issue, but there isn't anything available. No user guide, troubleshooting page, document, etc.
However, I see that the CLUE version is available in full mode from the IVM website (the website is recommended by the original developers).
Download: http://www.ivm.vu.nl/en/Organisation/departments/spatial-analysis-decision-support/Clue/index.aspx
Replace the installed version and then repeat the process. Additionally, go to Help > About and note the developer's contact email addresses or phones and contact them regarding this issue.