when did you download this BiofilmQ version? I could not reproduce your error, but I know we had an issue like that with a release a couple of weeks ago, which was corrected with the latest release v0.2.1. Try downloading the latest version from our website (https://drescherlab.org/data/biofilmQ/docs/usage/installation.html) and re-installing it. If the problem persists, please let me know.
By the way - we are also planning to upload a new release by the end of this week, which will include a few more global measurements, it might be worth waiting for that one to go online. In any case it is always worth checking for newer versions every once in a while and updating your BiofilmQ (you do not need to uninstall fist). We´re still actively working on improvements and new features and trying to include suggestions from users.