Additional TimeFrame Parameters in Optimization

I want to set an alternative TimeFrame (in addition to the timeframe selected for the cbot). I add this code into my bot:

        [Parameter("Display Pips Per Candle", DefaultValue = "Minute30")]
        public TimeFrame displayTimeFrame { get; set; }

That's all fine and good.

However, I want the optimizer to test a range of alternative timeframes. Normally, with a parameter set like this, the optimizer would allow me to select a range  of options - for example, the timeframe option in the optimizer has a tick box which, when selected, provides the full range of time options to test.

Setting a parameter like this does nothing other than set that single timeframe as an option. There's no tick box. Even when I add this following code, there's no change. The only timeframe available to the optimizer is the "Default" timeframe, which is not optimizing anything!

        [Parameter("Display Pips Per Candle", DefaultValue = "Minute30", MinValue="Minute5",MaxValue="Hour1")]
        public TimeFrame displayTimeFrame { get; set; }

It treats the "Default" timeframe as a static variable - there's an oxymoron for you - rather thn a variable from a range.

Is this frustrating. You netcha!

Why?

Simply because I'm trying to get the optimizer to return some results using a range of variables and one of the principle variables can't be tested!