I saw some difficulty in the wizard creating a green theme, so I opened the Preset Manager/ Data Bridge - Design dialogue.
I created a new theme which I called "lime". I wanted it to be "Lime" not "lime" and there was no rename option (an oversight in the extension perhaps).
I tried editing the theme to see if rename was an option there. It wasn't , but the dialogue that opened to edit the theme was not populated with the existing theme settings.
Next I tried to export the theme to see if I could make the changes to the exported theme and re-import it.
The exported zip file contains two xml files. The xml file for the theme is populated with all of the theme settings except the theme name. I am updating ecart right now, so I can't give it to you exactly, but it was something like:
<wa_preset type="object" name="<!-- No Defined Style -->">
or something similar where it should have been:
<wa_preset type="object" name="lime">
I changed that line and the file name to "Lime"
<wa_preset type="object" name="Lime">
and re-imported to get it right.