I've also noticed that when I click on:

 http://localhost/Karamasoft/ASP.NET4.0/UltimateMenu/v3.3/Designer/UltimateMenuDesigner.aspx

as shown in the UltimateMenu ReadMe file I get the following:

http 404 The Web Page cannot be found...

maybe this is something?

I do have IIS 7.5 Express installed on this machine. 

I'm using VS2010... 

No the sample web app that came with the installation does not work...

Double cheecked in the control panel installed programs list: Ultimate Menu 3.3 for ASP.NET 4.0

I navigate to the Designer folder and then open the UltimateMenuDesigner - VS2010 opens... then F5 to run the site..  I see in red Menu tree cannot be loaded. click here to see FAQ's  .... click then...

You need to download and install Microsoft Internet Explorer WebControls.

To download and install the IE WebControls (such as TreeView, TabStrip, MultiPage) used in Karamasoft UltimateMenuDesigner click on the link below:
iewebcontrols.msi  I click the link and start the installation process... Then I get the following error during the installation -

The specified path 'http://Mobile3-PC/webctrl_client' is unavailable.  the internet information service might not be running or the path exists and is redirected to another machine.  Please check the status of thei virtual directory in the internet Services Manager

Also when I click to add a menu item I get this error:

Server Error in '/Designer' Application.

---

Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.] MenuDesigner.MenuDesignerCore.FindNode(String itemID) +135 MenuDesigner.MenuDesignerCore.GetItemProperty(String itemID, String name) +49 MenuDesigner.MenuDesignerPage.ibAddItem_Click(Object sender, ImageClickEventArgs e) +89 System.Web.UI.WebControls.ImageButton.OnClick(ImageClickEventArgs e) +115 System.Web.UI.WebControls.ImageButton.RaisePostBackEvent(String eventArgument) +120 System.Web.UI.WebControls.ImageButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5563

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.237

Will I be able to use the designer?  Ultimately I would like to use the Ultimate Menu with a SQL database.

Okay  - I'm headed in the right direction - I learned that I somehow deleted the Default web site in IIS so I corrected that by:

In IIS 7 / 7.5

1. Right click on Sites folder and click Add Web Site…
2. Under Site name: type “Default Web Site”
3. Under Application pool: select DefaultAppPool
4. Under Physical path: “C:\Inetpub\wwwroot”
5. Click OK
6. Fortunately for me, the “Default Web Site” was created with the ID 1.
7. But just incase, if in your case the “Default Web Site” does not show ID 1 and if ID 1 is not in use.
8. Open command prompt as an Administrator
9. Go to C:\Windows\System32\inetsrv\config and type notepad applicationHost.config
10. Find “Default Web Site” and change id=”x” to id=”1”.
11. Save applicationHost.config
12. Now refresh IIS Manager and start the Web Site.

Now the link:

http://localhost/Karamasoft/ASP.NET4.0/UltimateMenu/v3.3/Designer/UltimateMenuDesigner.aspx

works...

I installed the iewebcontrols.msi successfully from your link but I'm still getting the Menu tree cannot be loaded.  Any Suggestions?

yes this happens just as soon as the page is opened...

When I click on the + sign to add a new item a New Item is added but to the right and looks Like: EX..  click the + sign 3 times...

Menu New Item New Item New Item