Liquid Rhythm is Push 1 compatible with Ableton Live 9 and Live 10. Liquid Rhythm is not currently Push 2 compatible or Push 1 compatible with Live 11.
An issue reported where a customer created an empty clip and pressed the User button on the Push and nothing happened, all the lights were out except for a flashing “User” light.
If this is your situation please make sure you have the latest Push firmware. You can find more information from Ableton here.
Also ensure you are using the latest Max For Live version; we recommend the last version of Max 7 with Live 9, while the bundled Max 8 with Live 10 should work (but you can also configure Live to use the latest Max 8 if necessary). You can download versions of Max from Cycling '74 here.