Thx very much Kingdomecome,
great tutorial.
Once you are trained it's easy.
Just create that mirror folder structure with the necessary files.
Then zip / tarbal the whole into a single compressed container.
That's your new extension.
Test it, put it into the tce-directory, restart and it's working.
Wonderful.
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That's when you are trained. If it's your first time, it might be slightly different.
There are a lot of possibilities for these nice typos, I'm addicted to. So maybe you have to debug half a day before you get through.