Somehow my grammar section has the status "Currently unavailable". I have been using it for years and have plenty of resources. Are there anybody who knows what it is?
Try following the instructions in this post to recreate the missing section: https://community.logos.com/forums/t/140062.aspx
The newer version of the Grammar section requires access to the Grammar Cross References Dataset. Check the sidebar at https://www.logos.com/product/52386/grammar-cross-references-dataset to see a list of packages that include this resource.
OK, so Logos has replaced it with a new dataset and requires payment for it. That's good business...
The linked thread explains how to set up your Exegetical Guide so that you get the exact same functionality and behavior as the old Grammar Section. There is no need to upgrade to the new dataset unless you wanted access to the new functionality offered by that dataset that was not available using the old section.