Custom Interval disappears when zooming out. This is caused when the view is updated and there is more than one custom interval.

When DateTime.MinValue is set as a value to the PeriodStart property, zooming out will result in an ArgumentOutOfRangeException. The same exception is thrown when the value of the PeriodEnd is lower than the zoom-in step.

When you select a time span at the beginning of the period, the left thumb is not visible. Issue is reproducible with our Fluent theme.

When SelectionEnd is equal to PeriodEnd, and PeriodEnd is at midnight (00:00:00), then selection title shows incorrect selection end.

To reproduce consider the following xaml:
    <telerik:RadTimeBar PeriodStart="1-Jan-2010 12:00:00 AM" 
                        PeriodEnd="31-Dec-2011 00:00:00 AM"
                        
                        SelectionStart="1-Jan-2010 12:00:00 AM" 
                        SelectionEnd="31-Dec-2011 00:00:00 AM"
                        
                        SelectionTitleFormatString="{}{0} - {1}"
                        />

PeriodEnd == SelectionEnd == 31-Dec-2011 00:00:00 AM, but title is: "01/01/2010 00:00:00 - 30/12/2011 23:59:59"

As in our app we display date with "dd MMM yyyy" format, the displayed selection end differs by one day from the real one, which is a serious issue.

The values of VisiblePeriodStart and VisiblePeriodEnd properties are not respected after runtime theme change. 

If the PeriodStart and VisiblePeriodStart is set to DateTime.MinValue zooming out using mouse wheel causes a crash. DateTime.Subract(TimeSpan value) method throws "ArgumentOutOfRangeException();". Looks like "TimeBarBase.CalculateLeftRightStep(this.SmallChange, centerOffsetPercentage, out leftStep, out rightStep);" does not calculate leftStep correctly.

When click and keep the mouse button down into the RadTimebar control and at the same time tap outside the application, InvalidOperationException is thrown.
The issue is reproducible on Window 7 OS.

Fix available in LIB Version 2016.1.328.

The value of the MinZoomRange property is incorrect after changing the the PeriodStart and PeriodEnd from code-behind.

Fixed in Q3 2014

RadTimeBar throws XamlParseException when current culture is arabic.

Workaround: Create a custom class that inherits from Telerik.Windows.Controls.TimeBar.SelectionThumb and explicitly sets the TitleFormatString property to your custom format string in the constructor. Edit the Template of the RadTimeBar control - find the SelectionThumb instance in the template and replace it with an instance of the CustomSelectionThumb class.

Add the ability to extend/contract the current selection by Shift-clicking. This can be used along with the "IsSnapToIntervalEnabled" property.

Enable snapping to PeriodStart and PeriodEnd as well, when IsSnapToIntervalEnabled is set to "true"

The selection element does not always show the correct range in MVVM scenarios, in which the view model validates the range. The problem is only present in WPF.