Since this took me a while to figure out the best method, I thought I would share.

If you are posting JSON data to MQTT and want to use a property of a topic to populate a label:

Posting JSON to MQTT:

Getting a value from a specific property of a topic:

Annoyingly, without the ability to set the retain flag and QoS in MQTT, UIflow's support of it remains just a toy.

In addition, we really need a flag that tells us when the MQTT connection has actually started because there seems to be a significant delay before it works.

@dimi Nice start but how do we include other libraries so we can interface to other systems over http/mqtt/etc?

There is an Arduino IDE stepper motor example listed on the M5stack site - I think it links to this forum. It is very simplistic, controlling a stepper to make a simple "clock" but it should be enough to get you started.

@chb Have you tried the M5ez library?

https://github.com/ropg/M5ez

Does anyone now have any updates on this question? It would be really helpful to get some more info.