I think I understand what your question is now. If you are wondering whether your BT download process on the Synology is going to be terminated properly or not, I'm afraid only the developer of the BT download program will know. The process will terminate upon receiving SIGTERM or SIGKILL for sure. However, the integrity of the temp files are usually unpredictable. If a program is well written, it will anticipate this kind of situation, and recover from it. For example, uTorrent seems to be doing just fine if you kill it randomly, but other program may leave some currupted files. If you cannot get the answer from the developer, you'd have to do the experiment yourself and see if it works.