I have the same game loaded on a dedicated server, and have been playing it for months with family who live around the country. The crafter NPCs are all max level, and usually stand around doing nothing for weeks, except eat all my cornbread. Even through the last dozen patches to the server, they never walk away, never disappear, never stopped working when i gave them a valid task...all is working as intended. The code is fine. I'm going to guess that any issues you experience is due to latency glitches between you and your server. That isn't something we can easily fix, even if we knew what the networking issue was exactly.