The current version of the mod (1.6.27) requires base >= 2.0.18 which is not currently the stable version of the game.
Any server on the stable branch will fail to start.

I mean, that's on purpose? Experimental version 2.0.18 has a choose-elem-button fix that allows module fill option to work again.

Understandable, thanks for the fast reply.

Releasing a mod version that requires something other than the stable version causes some issues, but I'll work around them on the servers.

Oh, I see. Another user also raised this issue on Github. Will keep it in mind for the future.

Although answered, I want to add that I also ran into this issue. I used to follow experimental server releases but with 2.0 I follow stable.

Same issue here. Our server won't start unless we remove the mod. This and Shortcuts for 2.0 are both using experimental branch for base dependency. this really needs to stop. It's shooting yourself in the foot by making your mod unusable for any players running a server on stable branch. Please Fix.

So this is an issue with a server mod updater that just downloads the latest available .zip without checking the requirements on base