There are no commits related to this bug yet, but once there are they will be in the master branch. The bug report on Github is the best place to track the progress. 1.6 is still a few months away. There will not be a 1.5.4.
You are correct. The Cyclops can only print materials that extrude at the same temperature. If you need to be printing materials at two different temperatures, the Chimera is the way to go.
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