css style like the background color for the pinned rows can be different from the rows in the grid to differentiate the rows

CartesianCustomLineAnnotation should allow for rendering options (2D, Bitmap, default) to allow for a consistent visual appearance.

It would be nice if the Telerik UI for WPF VSExtensions detected usage of UI for WPF in class libraries (e.g. a WPF UserControl Library)..

This would allow the Upgrade Wizard / configure Project wizards can also work on the class libraries, too.

This is a MVVM helper that could be used to decrease the coupling between the view models.

Please can you add xlsm file support to RadSpreadProcessing.

Introduce support for AutoCad files in a fixed document viewer.

In addition to the great nuget packages, could we also get Nuget packages with symbols baked in?

https://docs.nuget.org/ndocs/create-packages/symbol-packages

Improve the support for async operations. Currently, if the db data context is shared between the collection and another consumer, issues could occur.

When new product features are released it would be useful to show a short introduction for users.  View introjs.com to see a similar solution for web development

When MainView.xaml is opened, the designer throws NullReferenceException because the SelectedOutlookSection is not initialized.

Workaround: If SelectedOutlookSection is null, then initialize it to point to the first item from the collection of outlook sections:

public OutlookSection SelectedOutlookSection
{
    get
    {
        if (this._selectedOutlookSection == null)
        {
            this._selectedOutlookSection = this.OutlookSections.FirstOrDefault();
        }

        return this._selectedOutlookSection;
    }
  ...
}

The fix is available in R1 2017 SP1.

Currently if a column is bound to a field of type DateTimeOffSet it is not displayed using the culture like DateTime is. It would be nice if this is supported in the future

Add a property to the RadWindow, to enable a behavior, so that when the user attempts to focus on the parent window (while the modal is open), the modal window will flash.

You can see this behavior in other Windows applications that show modal dialogs.

One requires to create QueryableCollectionView on the UI thread.
Now there's going to be a .Count() call on the IQueryable passed into the constructor,
which will block the UI thread until it returns.
There might be various reasons why there is delay (unable to connect to DB,slow query, using a REST queryable provider, etc).

It would be nice if we could pass in the count ourselves.

Make the internal static class Telerik.Windows.Controls.WeakEventHandlerManager public.

In Excel it's easy to rotate the contents of a cell. In the Gridview, it's possible to rotate the contents of the header, but the result is a column header that resizes weirdly, and the workaround (at least the one I was provided) is clunky. How about a simple property like <telerik:GridViewDataColumn Header="Name" HeaderRotation="-90" /> 

For more details check here: http://jeremybytes.blogspot.com/2014/10/using-callermembername-attribute-for.html

Available in the R1 2017 SP1 Release.

Add additional properties to the ZipPackageEntry that describe the creation date, the last modified date and etc.

Add a possibility to create a ZipPackage with a password associated with it.

Ability to zip files bigger than 4 GB needed

Implement the "add file to existing archive" functionality