Maven dependency in IntelliJ disabling Run

[splicymusic]

EDIT: Apologies for posting this in the wrong section. I'll move it to issues

I'm importing this library with Maven in IntelliJ. Very oddly this appears to disable running my app. The green play buttons and menu items for running are all there but using them does... nothing. Commenting out the alpaca-java dependency and restarting IntelliJ allows running. (Simply re-importing all maven dependencies does not do the trick).

Has anyone else experienced this?

I've seen this kind of issue pop up a few times in reference to Gradle:
https://intellij-support.jetbrains.com/hc/en-us/community/posts/360000045539-RUN-simply-stopped-working-for-one-single-project-which-previously-worked-fine-no-changes-to-configuration-

Could the issues be related?

IntelliJ 2017.3 Ultimate Edition.