We already responded to you via support email and please do not send the same query in multiple windows. Anyway, I will copy the same here too.
1) If the system suddenly shuts down and somebody took that system when the files are decrypted: AxCrypt is a user-mode software and It is running on the operating system. The app(not only AxCrypt) will get cleared/exited when the operating system forcefully shuts down. In this case, How the AxCrypt application will work? Because the system itself closed forcefully. So, If the files are not secured and the system went to shut down, sorry to say the AxCrypt app will not handle this situation. Your unencrypted files will be unencrypted state only.
2) Yes, I agree, AxCrypt will not continue the encryption/decryption process if it gets an exception. We are already working on the issue and the same will get released as soon as possible.