Hello,
My add-on is localized to German, there should be no English words. Make sure you have German Firefox installed or install German language pack:
https://addons.mozilla.org/en-US/firefox/addon/deutsch-de-language-pack/?src=search
Please let me know to my support e-mail if it didn't help.
Best regards,
Juraj Mäsiar

Hello,
You can override any CSS style in my add-on. See the Options page / General tab / "Custom CSS styles:".
For example, to change color of dials heading, use this:

.dials > a > div > div {
background: lightblue !important;
}

And to make group list more colorful, use this:

#groups {
background-color: rgba(255, 209, 57, 0.6) !important;
}
#groups > .selected {
background-color: orange !important;
}

You can create also new styles, just inspect the element you want to change and create new CSS rule. However make sure to pick the theme - black or while, depending on whether your final theme will be dark or light.

If you have more questions, feel free to write me to my support e-mail.


Best regards,
Juraj Mäsiar

Hello,
That's actually a very good idea. I will put it on my todo list. I'm not sure when exactly but I should have more time soon.
Thank you for the idea, if you have more thoughts, please let me know to my support e-mail.

Best regards,
Juraj Mäsiar