Hello, and thank you for all the information you gave me. I thought the issue was potentially caused by the customization.
Unfortunately, I haven't been able to replicate the crash on an Ububuntu server with 8.4 2018-05-14 built 84191707. So, yes I confirm it. works without causing any server crash.
If you are able to replicate it, please report it as a bug attaching a sample database.
Getting a bugged environment I will be able to verify and escalate it to our dev managers and programmers.
I look forward to your reply.

Giuseppe
HansaWorld Italy