The shortcodes have changed in version 2. The equivalent to your old shortcode is
[op-is-open open_text="OPEN" closed_text="CLOSED"]
You can read more about the new shortcodes and its extended features at https://github.com/janizde/WP-Opening-Hours#op-is-open-shortcode
Update: You will also have to provide the corresponding Set id which you can see in the edit screen of the set, so when your Set id is 4 the shortcode would be:
[op-is-open set_id="4" open_text="OPEN" closed_text="CLOSED"]
In the section where you explain the shortcodes, you should REALLY add standard examples, so people can copy + paste a shortcode and then expand it from there.
Some people just try to figure out quickly how the plugin works (or want to make it work ASAP)… Examples also help greatly to understand the structure.
I guess this would improve the plugins popularity a lot. Just my $.02 😉
