Z21 App Consist Traction Settings

Hi

I'm struggling with the Z21 app traction settings to set up a consist.

Ipad or iPhone the result is the same. A consist that will only let me run at max 6SS.

I have entered the traction settings for both locos over a 1m stretch of track for speed steps 10, 15, 20 and 28.
(My settings will only allow each loco to be set at 28 speed steps. 128 is greyed out).
Settings look like this:
Reg Step Time
10 11.000000
15 5.000000
20 3.500000
28 1.500000

(Quite why the default requires accuracy to a millionth of a second beats me).

When running either loco individually it runs up to a good max speed as I slide my finger up to 28SS.
When running the consist I can only slide up to 6SS. I can't 'push up' above that. Hence the consist runs frustratingly slowly.

Any ideas anyone.

Rick