Problems with TMS MQTT with Delphi 11.3 and 12

I have Embarcadero Delphi V11.3 and V12 installed together.
I tried demo program and I wasn't able to connect with the broker.
i tried also last TMS MQTT version V2.0.8.0.

At moment my solution is to install only TMS MQTT library on Delphi V11.3, in this way. my program is able to connect to Mosquitto.

I think there are conflict with Indy Network connection library.

I cannot see any reason for connection issues when having installing and using the component from multiple IDEs.
What exact error do you get? Did you replace the default Indy library that comes with the IDE?

If I compile with Delphi V12 and run program, I have Runtime Error:
Project xxxx raised exception class EIdReadTimeout wiith message 'Read timed out.'.

This is an exception the Indy framework triggers.
It is a gracefully handled exception you can ignore.
When you run from the IDE, the IDE shows by default all exceptions, also those gracefully handled.
Either turn off this exception notification in the IDE or run the app outside the IDE.