We have introduced Cyclomatic Complexity measurement since version Q3 2013. For more information about it you could look at this blog post
or at our documentation
As far as it concerns the Maintenance Complexity, currently, we do not have it included in our roadmap but if you really wish JustCode to have such a feature, I would recommend you to post a feature request at our feedback portal
where it could gather votes and popularity which on its behalf will raise its priority.
If you have any further questions or remarks, please do not hesitate to contact us!