Installation of BSP is unable to proceed as the Mill executable is missing from both the project root and the PATH.

We have not yet implemented importing IntelliJ projects. I think the workaround is to import/convert the IntelliJ project to one of the supported formats and continue form there.

JetBrains has released new versions of its IntelliJ IDEA, WebStorm, and RubyMine IDEs for Java, JavaScript, and Ruby/Rails development, respectively.