In your Form1.Designer.cs, manually instantiate the List
like this
this.Values = new List<object>();
After you've added items, the Form1.Designer.cs
file will be recreated as per normal but the line above will be replaced by
this.Values = ((System.Collections.Generic.List<object>)(resources.GetObject("$this.Values")));
Alternatively, instantiate the list when you declare it.
private List<object> values = new List<object>();
public List<object> Values
{
get
{
return values;
}
set
{
values = value;
}
}