XML Schema generation creates empty import tag

[gpax]

I have been updating my schema in EA and when I generate my XML schema now, I get empty import tags generated before the include tags:
<xs:import namespace=""/>

I vaguely recall having got this before, though it's some time since I updated my schema and can't quite recall what I found to be the cause. I must have fixed any issues before as the final XSD files I used with code did not have these import tags in.

In case it helps, when I generate the XML schema I am getting warning messages after each validation pass:
Invalid connections found, these will be ignored