I thought I'd just draw attention to something in the release notes for NCrunch 2.15 -
http://www.ncrunch.net/download/showChangeLog?version=2.15.
Microsoft introduced quite a significant change in one of the later RCs of VS2015, in which they removed v4.5.3 of the .NET framework, replacing it with .NET 4.6.
In retrospect, this change would have broken NCrunch entirely. NCrunch v2.14 was designed to run its engine and tests using .NET 4.5.3 under VS2015 - a framework that no longer exists.
I'm sorry but there is nothing I can do to make NCrunch v2.14 work in the RTM version of VS2015. To use the product in this version of VS, you'll need to upgrade the product.