Hi folks,
Wondering what I'm doing wrong here... any assistance would be great.

I've created a new Lightning Out dependency app but using the generated code...

<aura:application access="global" extends="ltng:outApp" >
<aura:dependency resource="c:MyLookupComponent" />
</aura:application>

... if I try to preview it in the browser, I get the following unhelpful error message...

This page has an error. You might just need to refresh it.
Error during init [Action failed: ltng:outApp$controller$init [Incorrect usage of ltng:outApp. Refer 'Lightning Components Developer Guide' for correct usage]]

Note: from looking in the browser's console output, the app is definitely loading... i.e. I'm seeing:

execAuraJs: 1,223.14 ms
runInitAsync: 1,234.956 ms
runAfterContextCreated: 1,261.672 ms
runAfterInitDefsReady: 1,542.987 ms
runAfterBootstrapReady: 2,110.847 ms
appCreationStart: 2,116.047 ms

Any suggestions on potential causes and/or how to troubleshoot would be great. (I get the same error in both IE and Chrome.)

Thanks!
John