Cefsharp download window for showing progress in VB.Net

I am creating a browser using Cefsharp in VB.Net, and I have been trying to create a download window that shows the progress of the current download. I don't know if I am doing something wrong or if it is the way CEF works, but I put in a download handler by adding browser.DownloadHandler = New DownloadHandler to Form1_Load and creating a new class like this (with downloading being the form I created for showing the progress):

Public Class DownloadHandler
Implements IDownloadHandler
Public Function OnBeforeDownload(downloadItem As DownloadItem, ByRef downloadPath As String, ByRef showDialog As Boolean) As Boolean Implements IDownloadHandler.OnBeforeDownload
    downloadPath = downloadItem.SuggestedFileName
    showDialog = True
    downloading.Show()

    Return True
End Function

Public Function OnDownloadUpdated1(downloadItem As DownloadItem) As Boolean Implements IDownloadHandler.OnDownloadUpdated
    My.Settings.downloadpercent = downloadItem.PercentComplete.ToString

    Return False
End Function 
End Class

On the downloading form I have this code for showing the progress:

Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
    Dim percentcomplete As Integer = My.Settings.downloadpercent * 5
    Me.PictureBox1.Size = New Size(percentcomplete, 25)
End Sub

Private Sub downloading_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Timer1.Start()
End Sub

This may not be the best way to show a ProgressBar, but I have a picture box that just has a green bar, and the total width of the form is 500px. The code is telling it to read the PercentComplete setting put in My.Settings.downloadpercent, multiply it by 5, so when the progress in 100%, it will go across the whole form.

The problem is that the ProgressBar is not being updated to show the current progress. It goes a little bit, but then it just stops. Am I doing something wrong, or is OnDownloadUpdated not a good place to put that? Any suggestions of how to fix this?