If you are running internally using WAS Liberty then you can add the following to the Liberty server.xml to accept the CORS calls.
<cors domain="/DecisionService"
allowedOrigins="http://localhost:9090"
allowedMethods="GET, DELETE, POST"
allowedHeaders="accept, Request, content-type"
exposeHeaders="Request"
allowCredentials="true"
maxAge="3600" />
Alternatively if you launch the browser app using the Rule Designer's Internal Browser (Eclipse Preferences > General > Web Browser) then I find this sometimes avoids the CORS issue.
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Andy Macdonald
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