Thanks for your comments and link.
I have found the cause of the problem:
When I write the name in a new post, post’s address is changing (/%postname%/) and thumbnails do not work.
However, when I leave the name empty, post’s address will be /numbers – not letters, thumbnails plugin works!
So what I do is I write the name after the post is published with a thumbnail.
I hope it can be fixed in a new version, Sutherland?
I also tested “Test Providers” and “Test Image Downloading” – everything works fine.
So it must be the post’s name that is causing a problem for plugin..
Thanks again for your work!
