Hi Luis, sorry for not responding earlier 😅.
I am planning an initial release for Bevy 0.9, which should be ready in a few days.
If you would like to test the current version you can add the following to your Cargo.toml, or you could clone the repo and run the examples.

bevy = { git="https://github.com/bevyengine/bevy" }
bevy_terrain = { git="https://github.com/ku95/bevy_terrain" }

I am always looking for people willing to help develop/test/use the plugin.
If you would like to chat about its current state you might want to join the discord server 😄.

Hi again,
Your code runs just fine, but there is quite a limitation in having to use unreleased bevy. It introduces a large question mark about the support for any of the other libraries. Let me know if you need help binding bevy terrain to at least the latest bevy release.