Thanks for your report.
This bug has been added to the tracker:
https://winscp.net/tracker/1947

I'm sending you an email with a development version of WinSCP to the address you have used to register on this forum.

Steps to reproduce:
Open Executable, Close Logic Dialogue, Try to exit app. Error will be displayed.

WinSCP 5.18.1

Error message:
Invalid access to memory.

Stack trace:
(00CE6600)
(000861AF) ntdll.dll
(00072B31) ntdll.dll.KiUserExceptionDispatcher
(00019854)
(000198FE)
(00242771)
(00283ED5)
(0023E39C)

Status: unknown_rel_addr

I know how to reproduce the problem or the problem happens frequently enough. I wish to be contacted by the WinSCP team to help resolving the problem.