After two days and reading a lot of forum news, the editing problem of the templates is soluted. Also, when you edit the source code of the template, the code will no longer be scrambled. Here is how it works:
1. Create a template with Artisteer 3 (download on the website)
2. Save it as "Website or Blog"
3. Download and open "Kompozer - //kompozer.net
4. Open the saved website and edit it
You can also use Mozillas "Seamonkey"
Have fun