Now onto trying to merge the the SerialGateway and MQTTClientGateway. Need to see if it would be easier to merge the MQTTClientGateway into the new SerialGateway or the other way around. Time to study some code.

If I change the lines to this:
const char VAR_63[] PROGMEM = "UNKNOWN"; //Custom for MQTTGateway

And leave this line alone:
PROGMEM const char *VAR_Type[] = [<removed to keep short>]

I get this error:
MyMQTTClient.cpp:82:30: error: variable 'VAR_Type' must be const in order to be put into read-only section by means of 'attribute((progmem))'
PROGMEM const char *VAR_Type[] =

I tried const char VAR_Type[] PROGMEM = [ ]; and char const VAR_Type[] PROGMEM = ; but I get the same error. I"m going to do some reading on PROGMEM to see if I can find out what it does.

Has anybody tried to get this compiled with the development branch (1.4.1) with the RFM69 radios? I have been trying to get a successful compile, but no luck thus far. I do have it working with the stable branch, but I am not happy with the radios and would love to get this client working with the RFM69 radios. I have looked over the code and started to merge the two, but I am not a C++ programmer and have had some difficulty with the following error:
yMQTTClient.cpp:16:14: error: variable 'VAR_0' must be const in order to be put into read-only section by means of 'attribute((progmem))'
char VAR_0[] PROGMEM = "TEMP"; //V_TEMP
I tried some of the workarounds that I found (const char VAR_0) but then the GetType functions break and I do not understand enough of the code to correct that issue. Anyway, I thought I would check here to see if anybody else has made some headway.

Thanks in advance for any information / help.