1. Open project in CC4.01 eg. Camila / Coyote / Alika
2. Open Facial Profile Editor and click Edit Expressions
3. If Viseme section says "8+7 Phoneme Pair" click it to change to 1:1 Direct viseme set (it doesn't not matter if you choose to save a back-up or not)
4. Click .fbx and select either Clothed Character or Selected (with character selected)
5. (I needed to click OK on the warning message saying how many times left on my 30 day trial license I can export a character from CC4)
6. In the Export FBX dialogue window, choose Target Tool Preset: Maya and FBX Options: Mesh and Expression Sequence
7. Click Export and choose a file location and name. A progress bar window appears and disappears, then another, and during this bar's progress CC4 crashes with a pop-up like the image attached.

I have tried the above process two or three times with different characters on each of two different Windows 10 PCs, one of which was a fresh CC4 installation to try to work around this issue.

I tried the above without changing the visemes to 1:1 Direct and the export worked with 8+7 Phoneme Pair settings twice on the different PCs which were crashing when trying to export 1:1 Direct expressions sequences.

As a test I tried the above process but made one change: I changed Target Tool Preset to Blender instead of Maya. CC4 crashed again as with the Maya setting.