I have released a new version. I added Google Calendar support in Event Progress. And it's also possible to change where the settings are saved.

http://www.nordicfx.com/topbar

Looks good, have you started putting it together?

I have managed to put in the feature of recursive directories in Launcher. I have a problem with the icons, once I fix that I will release it. And I'm considering making the recursive directories optional.

That shouldn't be too difficult...

In the plugin create a new UserControl, not a Control. In the XAML of the new UserControl you can design your layout with any types of controls that you need. In the code-behind create properties for value, minimum, maximum or whatever you need to pass to the control.

In the plugin, place a WrapPanel which will align the new instances automatically from left to right. Make sure you remove width and height for the WrapPanel and width for the UserControl.
Instantiate a new UserControl and add it as a child in the WrapPanel. If the content is cut off, the play around with Margin on the controls.

Topbar
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UserControl
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WrapPanel
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Instance of battery UserControl