Top left click projects
Bottom left click start a new project
On the left Import your HTML Code Base
Import from select export folder
Source directory empty (more on this later)
Use Cordova (if you want the plugins)
Game project no
Continue
Intel XDK Forum has given instructions for Construct that are a bit confusing (to say the least)
https://software.intel.com/en-us/forums/intel-xdk/topic/607195
I have built without the www directory and got no errors so ignore Intel's instruction unless you have a problem I suppose.