From what you are telling me, I *think* the gradle support is correctly installed. If it were not, then the Gradle import wizard would not be available for you to use at all.
The error: Could not resolve all dependencies for configuration ':classpath' ...
seems like actually an error caused by some problem in your own build script (I can not say 100% sure, but that would be my guess right now :-)
For some reason gradle is not able to resolve dependencies "bmushko:gradle-tomcat-plugin". These seem like dependencies specific to your project?
Maybe these dependencies are spelled wrong, or they are not available on any of the repositories you configured
gradle to look for dependencies in.
Can you build the project succesfully using gradle on the commandline?
Kris De Volder -- SpringSource