I know I am not supposed to report a bug without adequate screen capture video and the ability to recreate the issue - but, I can not identify a specific thing that cis causing this...but it's only been in the last couple of versions. The program frequently (and by that I mean it has done it 7 or 8 times today alone - as well as or the past several days) just stops running - no errors, no crash reports generated - it just puts up the spinning ball and stops running - when clicking on the icon in the system dock, it states that the application is not responding and the only recourse is to force quit xLights and start it back up again. I thought it might be only when I was using arrow keys to move an effect - so I turned on screen capture but of course then it didn't happen. It happened adjusting setting in the fire effect, adding a layer above in the grid, moving effects up a layer with the arrow, moving effect to the right with an arrow key, during the render process, upon clicking save, when expanding the length of an effect (a picture) by dragging on the pictures right handle...etc. I have tried just letting the screen capture run - but then I have a massive video file and, of course, no application not responding recorded because it never happens when I'm trying to catch it!!!!! I can also comment that when i restart xLights always tells me there is a newer file and asks if I want to use it and to replace my xml file - I always say yes - and then it always says it can't create a back up. Sorry there is no better data to submit on this - but it sure does happen a lot! I am on a Mac running 2018.32 (I know .33 exists, but I read o several problems on FB and was waiting to see if it was truly stable before moving up to it)...though I guess my experience with 30-32 has been that it seems to do this lock up thing a lot, too.Of course, when it lock up like this no cash report is generated because the program ceases to exist in the computer's memory! And - yes, I did just let it sit for several hours (3 an 1/2 hours to be more precise) to see i it would "clear" the lockup on it's own - it did not.