Quote from Mirillis facebook page:
Some of our users may experience problems where Action! Is crashing game or application after the recording process is stopped. Recorded game or application usually crash and recorded video becomes broken and unusable.
This problem occurs with Intel HD series and Nvidia Optimus computers. The cause of this problem is the newest Intel Graphics Drivers update (9.18.10.3165)
Unfortunately this problem, which also occurs with other vendors applications is caused by faulty Intel drivers. We strongly recommend reversing your drivers version to the previous one where the issue doesn't occur (9.17.10.2932). We have already informed Intel about this problem.
This also affects exporting process in Action! and Splash PRO EX when Hardware Acceleration is turned on.