Problem with file names

At the moment we sometime face the problem, that Robohelp is suggesting another Filename as the title is showing. We can`t reproduce this problem but with some file names we have a problem like you can see in the screenshot.

The reason is surely not the "ä" letter, because we already use other titles with "ä", "ö", "ü" which are showing the same file name as title name. But as we are not able to reproduce this problem i think this is not easy to check.

But what is really annoying is the fact that when we change the title name after saving it, the file won`t be overwritten. Robohelp is creating a new file in windows with the new file name. Afterwards we are not able to delete the first file in the author`s content. So we also have problems in our version control afterwards as the file is missing...

Does someone have a solution for this?