Newbie questions about MAX_CUL and device configuration

[disney]

I'm sorry I am probably going to ask a number of dumb questions over the next few weeks as I try to sort out my FHEM installation.

For heating I have a MAX cube reflashed as a CUL and EQ3 MAX valves and wall sensors and I use some code from www.ply.me. to control my boiler using a Sonoff-Tasmota switch. Everything seems fine but I am not clear on a few points even after reading the documentation:

a) What is the best way to verify/minimise CUL credit usage?

b) Should I include wall sensors in a group with the radiator valves - the online help seem to suggest NO but the option is available on for the wall sensor.

c) What do MAX! groups really do?

d) Is there a way to retrieve the device associations to check they are associated properly?

[Beta-User]

Sorry for nobody answering your questions here for weeks...

As the number of MAX users seems to be decreasing, imo, you should open up a seperate thread in the MAX part of the forum (pointing on your questions here, e.g. by just citing it). Most likely the MAX maintainer and other MAX users do not visit this part of the forum regularly.

Kind regards,

(non-MAX-using) Beta-User

[Wzut]

a) What is the best way to verify/minimise CUL credit usage?
b) Should I include wall sensors in a group with the radiator valves - the online help seem to suggest NO but the option is available on for the wall sensor.
c) What do MAX! groups really do?
d) Is there a way to retrieve the device associations to check they are associated properly?

a. dont use / minimize set commands 
b. I don't really know at the moment. I'm still investigating
c. Max groups map the rooms in the Original Cube software. IMHO important if you have more than one valve in the same room and each valve has to talk to its brother directly
d. no and at the moment I don't know of any solution