really-static support

[mp77]

Eric,

I am trying to setup Really Static plugin. It works fine on my dev box.
I tried the same setup on my staging server (Unix).
But on this server I am getting "Please wait! Another really-static instance is running!" when I try to update a new post.
I am able to manually generate all the files but if I update the post, it saves the post content but fails while publishing static file.

Need your help URGENTLY.
Also would like to know if there is any premium/paid version for this plugin and how much it costs.

Thanks,
Manan