I created a simple page of WebGrid based on your description. All its columns created at runtime.

protected void WebGrid1_PrepareDataBinding(object sender, ISNet.WebUI.WebGrid.DataSourceEventArgs e)
{
    string Columns = "";
        
    if (!IsPostBack)
    {
        // clear all columns before repopulated
        WebGrid1.RootTable.Columns.Clear();
        WebGrid1.RootTable.SortedColumns.Clear();
        WebGrid1.RootTable.GroupedColumns.Clear();
        WebGrid1.RootTable.FilteredColumns.Clear();

        Columns = "EmployeeID,LastName,FirstName,Title,BirthDate,HireDate,Address,City,Region,Country";
        string[] ColumnsCollection = Columns.Split(',');

        foreach (string Column in ColumnsCollection)
        {
            WebGridColumn col = new WebGridColumn();
            col.DataMember = Column;
            col.Caption = Column;

            WebGrid1.RootTable.Columns.Add(col);
        }
    }
}

Following list shows the step-by-step that were done on my local test in order to test the reported problem.

1. View RowDisappearWhenFilterApplied.aspx sample file in browser.
2. After the page loaded, apply filter on BirthDate column through the filter bar. For example: filter text is: 01/01/1960 00:00:00 and filter type is: Less Than.
3. Move down to a record. For example: "Steven Buchanan" record. Then modify its "City" from London to Manchester.
4. Save the record by pressing Shift + Enter.
5. The record doesn't disappear from the grid.

I enclosed my simple sample as attachment. Please have the sample evaluated on your end and let me know if you find anything that I might miss during my attempt to reproduce the problem.

Please try to use one of the following snippet code to change checkbox value.

function SetCheckBoxValue(){    // retrieves WebGrid's object    var grid = ISGetObject("WebGrid1");
    var selectedRowObj = grid.GetSelectedObject().ToRowObject();
    var checkboxCell = selectedRowObj.GetCells().GetNamedItem("MyCheckboxColumn");
    var cellElement = checkboxCell.GetElement();

    // use following code to make checkbox checked
    cellElement.children[0].checked = true;

    // use following code to make checkbox unchecked
    cellElement.children[0].checked = false;

    // or invoke click() method to simulates the click event on checkbox
    cellElement.children[0].click();
}

Hope this helps.

Thank you for the sent log file. I will check the logfile and will get back to you as soon as possible.

Edited on October 8, 2015 4:00 AM
Reason: Update test result

I tested the installer problem in a fresh PC. It has Windows 8.1 Professional and VS 2015 installed. Please see the attached video which shows the install test.

Could you please right-click on the installer file then select "Properties" from the context menu? The screenshot below shows the "Properties" window of the installer that I use during testing. If you have older version of installer, please try to re-download and let us know if the problem still persist.

OnExport server-side event of WebGrid will suits your requirement well. You can always change the ReportPath property and other report-specific property such as paper-type, orientation etc, in the ReportInfo object provided by the event argument in OnExport event.

Following snippet code shows how to set Margin and font.

protected void WebGrid1_Export(object sender, ISNet.WebUI.WebGrid.ExportEventArgs e)
{
    // set Font size and Font family
    e.ReportInfo.DynFonts = new DynARFonts(new Font("Tahoma", 15), null, null, null, null, null, null, null, null);
        
    // set Margin size
    e.ReportInfo.DynMargins = new Margins { Bottom = 0f, Left = 0f, Right = 0f, Top = 0f };
}

This should helps.

Sorry for any inconvenience this problem may have caused you. This problem has been forwarded to WebCombo development team. It is filed under ASPNET-187.

Should I heard anything regarding ASPNET-187, I will let you know by updating this thread.

Edited on October 19, 2015 3:15 AM
Reason: provide solution.

If you are experiencing this issue when create WebCombo programmatically, set the ResultBoxWindowType of WebCombo's LayoutSettings to Normal should resolve the problem.

I modified Programmatic.aspx sample of WebCombo by adding a line of code in combo_InitializeLayout LayoutEventHandler and find that the reported problem is no longer persist.

protected void combo_InitializeLayout(object sender, LayoutEventArgs e)
{
    // Setup Behavior
    WebCombo combo = (WebCombo)sender;
    combo.DataTextField = "ContactName";
    combo.DataValueField = "CustomerID";
    combo.LayoutSettings.ResultBoxWindowType = DisplayType.Normal;
}

Please let me know if you have different result.