I have a small compose example app that I've been updating as the dev releases are made, and dev15 and dev16 have been challenging. Specifically, I'm finding on dev16 with Android Studio 4.2 Canary 7, I can no longer see any previews. The preview window just keeps telling me to compile the app. The app was based off the Empty Compose Activity example initially, and the code compiles. Would be happy to drop the code somewhere if people want it.

I Have the same probleme

Previews seem to be broken in Canary 7, Canary 6 works for me though https://kotlinlang.slack.com/archives/CJLTWPH7S/p1595516337213000

Is there a way to download previous versions of AS canary?

This issue appears to be tracked here: https://issuetracker.google.com/issues/162000445