I have also had this problem. The plugin installs but when I click activate it refreshes, has the message “plugin activated” at the top, but on the plugins page it is still shown as not activated.
I deleted the plugin and tried again to no avail.
The very first time I installed and activated it appeared, momentarily, but said I didn’t have access to the calendar section in posts (I am full administrator). Then since then it hasn’t activated at all.
Please help!
