For the ConfigurationProperty to work, the type used must be associated with a TypeConverter than knows how to convert from a string. ConfigurationProperty does have a Converter property, but alas, it's read-only. And, that's really bad luck, Version does not have an implicit TypeConverter declared either.

What you can do though, is add a TypeConverterAttribute to the Version class programmatically, and it will work around all these issues. So you need to basically call this line once in your program before accessing the configuration:

TypeDescriptor.AddAttributes(typeof(Version), new TypeConverterAttribute(typeof(VersionTypeConverter)));
// ... you can call configuration code now...

with the following custom-made VersionTypeConverter:

public class VersionTypeConverter : TypeConverter
{
    public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
    {
        return new Version((string)value);
    }

    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
    {
        if (sourceType == typeof(string))
            return true;

        return base.CanConvertFrom(context, sourceType);
    }
}