I need advice on the correct way to use a LUT file transform in an OCIO processor. My results when using a FileTransform look different than in Nuke, with whites appearing more subdued using the test LUT I have. Am I doing this right?

My normal OCIO processor looks like this:

DisplayTransformRcPtr transform = DisplayTransform::Create();
transform->setInputColorSpaceName(colorSpaceName);
transform->setDisplay(displayName);
transform->setView(lookName);
transform->setLinearCC(gainTransform);
transform->setChannelView(swizzle);
transform->setDisplayCC(exposureTransform);

processor = config->getProcessor(transform);

However, I also allow bringing in an external LUT file, and I use it like this in lieu of the DisplayTransform:

FileTransformRcPtr fileTransform = FileTransform::Create();
fileTransform->setSrc(path);
fileTransform->setInterpolation(OCIO::INTERP_LINEAR);

GroupTransformRcPtr group = GroupTransform::Create();
group->push_back(gainTransform);
group->push_back(fileTransform);
group->push_back(exposureTransform);

processor = config->getProcessor(group);

I'm using the same display shader for both.