I've added the class to the project, added it to the Toolbox and now I'm working on the test page. However, I found, that ArrowUpImageUrl properties are defined as string and therefore don't allow me to pick the Image using the Browse button.

Do you know if this is easy enough to adjust to allow them to be added using Browse button?

Here is the definition:

  [Description("The url of the image shown when a column is sorted in ascending order."), DefaultValue(""), Themeable(true), Category("Appearance")]
        public string ArrowUpImageUrl
        {
            get
            {
                string str = ViewState["ArrowUpImageUrl"] as string;
                if (str == null)
                    return string.Empty;
                else
                    return str;
            }
            set
            {
                ViewState["ArrowUpImageUrl"] = value;
            }
        }

        protected virtual string ArrowUpImageUrlInternal
        {
            get
            {
                if (string.IsNullOrEmpty(ArrowUpImageUrl))
                    return Page.ClientScript.GetWebResourceUrl(this.GetType(), "skmControls2.ArrowUp.gif");
                else
                    return ArrowUpImageUrl;
            }
        }
        #endregion

>>
>>So, should I just add cs files into app_code ? I did it yesterday already. I also added js and images to the appropriate folders.
>
>You need to pick the method of integrating this new control - either leave it as another project with it's own embedded images, or include the code into your existing project. Leaving it as an external project is probably easiest, since you don't have to make a lot of changes to the code for the control.
>
>If you decide to integrate it into your existing project, you will have to make changes to it and your project to get it to work correctly.
>
>>Should I delete the items I added yesterday to the toolbox?
>
>It depends on which project you added those controls from and how you've decided to integrate the control (as per above).
>
>>Ok, I'm going to try and go ahead...