Hi, Karsten,
I'm glad to report, that in the latest version we uploaded this weekend, we have added exact the feature you have asked in this email thread :)
Now we allow version string to be updated. Please go to project settings page, find "version list", and click the version string you want to update.
You will find an "Update" button next to the "Add" button along with the edit box:
In the screenshot above, edit 1.0_08 in the edit box, and click "Update" button will update version 1.0_08.
Please give it a try and let us know if any questions.
Sincerely,
-vincent
P.S:
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