https://www.screencast.com/t/OQyCn2jM

Reminders popup outside the page that the scheduler is used.
Because re-adding the same scheduler in many pages is very bandwidth consuming so what about creating a minified scheduler control for reminders so the user will be reminded in all pages about events.

When the timezone of the client is before UTC (e.g. UTC -1 or UTC -3) if you use the calendar for navigation, you will be navigated to the day before the selected one.

https://www.screencast.com/t/KlQtYDOxl

Workaround: 

var $ = $ || $telerik.$;
var $T = Telerik.Web.UI;
var $TS = $T.Scheduler,
$TSR = $TS.Rendering,
$DateTime = $TS.DateTime;
var $SB = Telerik.Web.StringBuilder,
timePerMinute = 60000,
timePerHour = timePerMinute * 60,
timePerDay = timePerHour * 24,
daysInWeek = 7,
roundedCornersHeight,
anchorDateFormat = "yyyy-MM-dd";

$TSVM = Telerik.Web.UI.Scheduler.Views.Month;
$TSVM.Model.prototype._createTimeSlot = function (rawIndex, startTime, element) {
    if (startTime.getHours() == 23) {
        startTime = $DateTime.add(startTime, 2 * timePerHour);
    }

    return new $TSVM.TimeSlot(rawIndex, startTime, element);
}

$TSVM.Model.prototype.getTimeSlotFromDomElement = function (domElement) {
    var rawIndex = this._getRawIndexFromDomElement(domElement),
                startTime = this._getTimeFromDomElement(domElement);
    if (startTime.getHours() == 23) {
        startTime = $DateTime.add(startTime, 2 * timePerHour);
    }

    return new $TSVM.TimeSlot(rawIndex, startTime, domElement);
}


Telerik.Web.UI.Scheduler.Rendering.MonthViewRenderer.prototype._updateColumnHeaders = function () {
    var renderer = this,
        dayHeaderDateFormat = this._model.get_dayHeaderDateFormat(),
        firstDayHeaderDateFormat = this._model.get_firstDayHeaderDateFormat(),
        currentMonth = renderer._owner.get_selectedDate().getMonth(),
        visibleRangeStart = renderer._model.get_visibleRangeStart();

    $.each(this._contentTables, function () {
        var dateLabels = $("td div.rsDateWrap div.rsDateBox a", this),
            dayStart = visibleRangeStart,
            weekDayIndex = 0,
            weekStart = new Date(dayStart.getTime());

        dateLabels.each(function () {
            var isFirstVisibleDateOfMonth =
                    $DateTime.subtract(dayStart, visibleRangeStart) == 0 &&
                    dayStart.getMonth() == currentMonth;
            var dateHeaderText;

            if (renderer._owner._renderMode == $T.RenderMode.Mobile) {
                dateHeaderText = dayStart.getDate().toString();
            }
            else if (dayStart.getDate() == 1 || isFirstVisibleDateOfMonth) {
                dateHeaderText = dayStart.localeFormat(firstDayHeaderDateFormat);
            } else {
                dateHeaderText = renderer._getFormattedDateText(dayStart, dayHeaderDateFormat);
            }

            this.href = "#" + dayStart.format(anchorDateFormat);
            this.innerHTML = dateHeaderText;
            this.title = dayStart.localeFormat(Sys.CultureInfo.CurrentCulture.dateTimeFormat.ShortDatePattern);

            var otherMonthCell = currentMonth != dayStart.getMonth(),
                dateWrapElement = this.parentNode.parentNode.parentNode;

            $(dateWrapElement).toggleClass('rsOtherMonth', otherMonthCell);

            if (weekDayIndex == renderer._weekLength - 1) {
                // Move to the next week, skipping invisible days.
                weekStart = $DateTime.add(weekStart, 7 * timePerDay);
                dayStart = new Date(weekStart.getTime());
                weekDayIndex = 0;
            } else {
                dayStart = $DateTime.add(dayStart, timePerDay);
                weekDayIndex++;
            }
            if (dayStart.getHours() == 23) {
                dayStart = $DateTime.add(dayStart, 2 * timePerHour);
            } else if (dayStart.getHours() == 1) {
                dayStart = $DateTime.add(dayStart, -timePerHour);
            }
            if (weekStart.getHours() == 23) {
                weekStart = $DateTime.add(weekStart, 2 * timePerHour);
            } else if (weekStart.getHours() == 1) {
                weekStart = $DateTime.add(dayStart, -timePerHour);
            }
            // Wrappers are cleared here to avoid second
            // traversal of the cells.
            renderer._clearExtraWraps(dateWrapElement);
        });
    });
}

The Button text initially shows "Never", even though the appointment has a different recurrence. https://www.screencast.com/t/55Rl1CSa7F7y

This doesn't work: apt.Description = DescriptionText.Text;

There is a display issue when using the agenda view - if there are fewer than 4 events displayed then clicking on the date range in the header shows a calendar which is clipped at the bottom. Presumably this is due to it being constrained by the height of the events area. This occurs even though there is plenty of height available to the control. Please see the attached screenshot which is taken from your demo site:
http://demos.telerik.com/aspnet-ajax/scheduler/examples/overview/defaultcs.aspx

Hello

It would be good to have the calendars grouped vertically and to have the time displayed horizontally. Please see attached screenshot

Regards
Peter