I received a popup after changing a bunch of channel assignments in the layout tab. When I tried to open one of my sequences to make sure everything worked correctly, I got the popup.
The popup is
"Program C:\Program Files (x86)\xlights v32\xlights\xlights.exe
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information"
When I clicked ok to this popup, I then got an "xlights stopped working" popup and I had to close the program.
I am running v56. When I reopened xlights and rendered the sequence, all is good; no problems.
I didn't have any crash reports to attach. By the way, I had run the check sequence subroutine and there were no channel conflicts anywhere.