Writing structure to /tmp/sbt-structure.xml...
Hi! The blog post says:
You can always select EAP or Release to revert to a more stable build; alternatively, you can download any Scala plugin build from https://plugins.jetbrains.com/plugin/1347-scala/versions.
So, should be relatively easy. And, in any case, it should be possible to download and install any desired version of the Scala plugin manually.