[isatrader]

Those averages mirror the price MAs.  I've been plotting the cumulative advance / decline and cumulative advance / decline volume lines (well, very close to) but I've used 50, 200 and 260 days, with the latter representing about a year.  Switching one to 150 to mirror the price MA seems logical.  In the shorter turn I'm getting the impression 200 days may be a little slow, it confirms what has already started or was recently finishing.

Regarding the MACD, I've recently started plotting the MACDs of these two lines, with the most commonly used periods.  I'm wondering whether the '1,200,1' MACD really is a MACD.  Effectively it is just a plot of the price minus the 200 day MA.  So surely it is some form of momentum indicator?

I use the 200 day plot the same way as the Momentum Index, in that crosses below the zero line or a break down from an established long term range towards the zero line are things to take note of, as it is a long term indicator. So yes, is also used for confirmation purposes as it is often one of the last things to break down.

The standard (12,26,9) MACD line chart is the 12-day Exponential Moving Average (EMA) less the 26-day EMA, with a 9 signal line. So the '1,200,1' MACD is the 1 day Exponential Moving Average (EMA) less the 200-day EMA. So it is a little different than the plot of the price minus the 200 day MA, as that uses a simple day MA and not the Exponential Moving Average. But the difference is fairly minor, so could probably lose it.