When uprating the row details data, the data does not update in the UI. You have to resize the window, or collapse then expand the row details to see the updated value. 

The behavior happens in 7.0.0 version. In 6.8.0 it works as expected. 

When the selected item is set initially, the selected style is not applied to the row/cell.

Workaround: You can use a Dispatcher to workaround the issue, code looks as follows:

this.Dispatcher.StartTimer(TimeSpan.FromMilliseconds(200), () =>
        {
            if (dataGrid.SelectedItem == null)
            {
                dataGrid.SelectItem(viewModel.PersonCollection.First());
            }
            return false;
        });

When a Picker is used in a CellEditTemplate, and when in edit mode, when I click on the arrow of the Picker - the picker does not open. It only opens of I click the text in the Picker.

        <DataTemplate x:Key="template1">
            <Picker ItemsSource="{Binding Item.Categories}" />
        </DataTemplate>

        <telerik:RadDataGrid x:Name="dataGrid"
                             AutoGenerateColumns="False">
            <telerik:RadDataGrid.Columns>
                <telerik:DataGridTextColumn PropertyName="Name" />
                <telerik:DataGridTextColumn PropertyName="Category" CellEditTemplate="{StaticResource template1}" />
            </telerik:RadDataGrid.Columns>
        </telerik:RadDataGrid>

A work-around is to not use a Picker, but use a RadComboBox.

Header Text, group header text, do not display some languages characters like Chinese, Thai, etc.

The root reason for this is the fact that the Skia APIs used to draw the text does not support automatic character fallback.

Workaround:

for header text:

<telerik:DataGridTextColumn.HeaderContentTemplate>
    <DataTemplate>
        <Label Text="your text"></Label>
    </DataTemplate>
</telerik:DataGridTextColumn.HeaderContentTemplate>

group header text

<telerik:RadDataGrid.GroupHeaderTemplate>
        <DataTemplate>
            <Label Text="{Binding Group.Key}"/>
        </DataTemplate>
</telerik:RadDataGrid.GroupHeaderTemplate>

column:

<telerik:DataGridTextColumn HeaderText="Name" >
    <telerik:DataGridTextColumn.CellContentTemplate>
        <DataTemplate>
            <Label Text="{Binding Name}"/>
        </DataTemplate>
    </telerik:DataGridTextColumn.CellContentTemplate>
</telerik:DataGridTextColumn>

Application Crashes if we delay the column creations after the collection is set.

No crash if we remove the delay.

Provide a style property for the text in grouping panel. Currently you can style the border, background color and change the header text of the panel. For example:

<Style TargetType="telerik:DataGridGroupingPanel">
    <Setter Property="BackgroundColor" Value="Red"/>
    <Setter Property="HeaderText" Value="Hello to group"/>
    <Setter Property="CornerRadius" Value="10"/>
    <Setter Property="BorderThickness" Value="2"/>
    <Setter Property="BorderColor" Value="Blue"/>
</Style>