I'm currently working on version 4.0 of the opentherm gateway firmware. Since I don't use all of the available features myself and I only have one boiler and thermostat, it would be helpful if other people could test the firmware with their equipment to make sure the new firmware will work with as many different types of devices as possible.
The firmware contains a number of new features requested by users on this forum, so it may well be worth your while to check it out.
The firmware is available at a special opentherm gateway alpha/beta firmware page. The new features are also listed on that page.
Please report here if you find any bugs or other problems with the firmware.