I just discovered a VERY simple and fast way to get and set Firebase data without using the GET or SAVE blocks (which has all sorts of asynchronous issues).
The 2 any button click blocks below return the same data. Just put the GET block KEY variable into the CLOUD variable name and PRESTO. You have a synchronous call to firebase!
Similarly, you can set data anywhere in the JSON Hierarchy using cloud variables. Both of the examples below update Firebase, but the CLOUD based solution does not have the timing issues of the SAVE Block