Libre (5.4.1 and 5.3.6) won’t create a new DB in Base. MBP, Sierra 10.12, 16GB RAM, SSD. Program just clocks (color wheel) after clicking ‘Save’.
Make sure you have latest version of Oracle JDK installed (not JRE). Also under LibreOffice > Preferences:
Under Advanced make sure Use a Java runtime environment is checked and the JRE (in the JDK) is selected.