Hi @JouniM,
Welcome to the community
Can you upload a screenshot of the screen where you are stuck ?
What type of endmill did you create and try to edit ?
Are you using a comma or a dot in numerical values ? Do you have any issue beyond the tool database menu to use numerical values in e.g shapes dimensions or toolpaths ? If so it may be due to the fact CC is not quite fully internationalized, and “.” must be declared as the decimal separator (the way to do this depends on whether you are using Windows or MacOS, see this thread for the Windows example)