If you are on HA 0.68 you get the latest one I made on github. The first one did not work with 0.68 - because 0.68 now support more than one maxcube. (Was release about the same time as i uploaded the first version)
In the next HA version the pull request is merged .so you can get it here if you can’t wait:
https://github.com/home-assistant/home-assistant/blob/dev/homeassistant/components/maxcube.py
(You place it in custom_components, And when you update to next HA version you can remove it)
Note that “update_interval” has been renamed to scan_interval to be more consistent with other components.