We really don't expect that you would be able to do that. NXOpen methods are intended to work within the framework of the ugraf.exe, and ITK calls are expected to work in the Teamcenter executable. The two programming toolkits are mutually incompatible.
However, much of what used to be available only in ITK is now available in SOA, and in recent releases, the TC SOA library is available in the NX installation folders. (I think by default it is zipped, and you have to expand it to use it.)
If you have NX10 or NX11 installed, navigate within your NX folders to ...UGOPEN\SampleNXOpenApplications\C++, and then there are a couple of examples:
Read the directions carefully if you decide to test this. It works, but attention to detail is important.
You can create a ITK user DLL that contains functions, which are called from NX using the PDM_invoke user function.
So you have two separate coding projects.
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