DNNSkins.com

Hi All,
I am learning how to create skins. My skin is correctly applied to my page but when I add a module I can't see the new module in my page. Could anyone tell me what is wrong with my skin ?

Also I created a page with the default skin. I added a common module and I inserted an image. It works well but when I try to apply my new custom skin I get the error message below:

Exception Details: System.ArgumentNullException: Value cannot be null.
Parameter name: file

Source Error:
Line 134: { Line 135: var fileInfo = FileManager.Instance.GetFile(portalSettings.PortalId, portalSettings.LogoFile); Line 136: headerImage.ImageUrl = FileManager.Instance.GetUrl(fileInfo); Line 137: } Line 138: else

Source File: c:\Documents and Settings\WEB DEVELOPER\Mis documentos\My Web Sites\dotnetnuke\ErrorPage.aspx.cs Line: 136

Stack Trace:
[ArgumentNullException: Value cannot be null. Parameter name: file] DotNetNuke.Common.Requires.NotNull(String argName, Object argValue) +48 DotNetNuke.Services.FileSystem.FileManager.GetUrl(IFileInfo file) +49 DotNetNuke.Services.Exceptions.ErrorPage.OnLoad(EventArgs e) in c:\Documents and Settings\WEB DEVELOPER\Mis documentos\My Web Sites\dotnetnuke\ErrorPage.aspx.cs:136 System.Web.UI.Control.LoadRecursive() +50 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627

My skin is below:
<%@ Control language="vb" CodeBehind="~/admin/Skins/skin.vb" AutoEventWireup="false" Explicit="True" Inherits="DotNetNuke.UI.Skins.Skin" %>
<%@ Register TagPrefix="dnn" TagName="SOLPARTMENU" Src="~/Admin/Skins/SolPartMenu.ascx" %>