If I translated your original support message correctly (my German is not too good and so I was relying on a translation service), it appears you are expecting to use the counter to count visitors to your site. This counter is not designed to do that and in no way states that it does.
You contacted me 3 times over the Easter holiday period (a public holiday in Australia). I responded to those messages immediately after the holiday.
This is a freely available plugin originally written for fun. It has continued to be developed and supported in my spare time. There are hundreds of happy users of this plugin and I’ve spent many many hours offering support totally free of charge. If somebody chooses to show their appreciation though a donation they are free to do so, I am not forcing them to nor offering a crippled trial version of the plugin that must have a paid for version to be of any use.
Quite frankly I consider it totally unreasonable to leave a bad review on plugin because you have totally misunderstood what the plugin actually does and consider it broken. And that somebody does not instantly respond to your support requests during a public holiday.