Thank you for your answer.
You are right, but:
When I select Joomla as CMS, then Wordpress is preselected. For a beginner like me who don't look on the style selection it's confusing. Now I know this but my first contact with TT was frustrating because I missed, that there was a Wordpress logo and export didn't create a Joomla Template, although I selected Joomla at programm start.
In my opinion it would be better that the style is preselected because I made a selection already in the first screen. If I have to set the style type again, the first selection screen is needless.