Hi Matthew,
Sorry for the delay in getting back to you.
All our 4.0 version assemblies will be working with .NET Framework 4.5 also. Since Microsoft released the .NET Framework 4.5 is an in-place upgrade to 4.5, we do not need to have separate two assemblies for both frameworks. It will create an issue only when we have 4.5 Framework specific features, but you are using that feature in 4.0 Framework targeted project.
At present, we have not implemented new features that targets to 4.5 alone in our controls. However, we are considering your request in any of our upcoming releases and will update you once it is included in our roadmap.
Please let me know if you have any queries.
Regards,
Sivaguru S