Thank you for your very informative reply.
I notice you are using a slightly newer FreeCAD version than I am. I've now updated mine to be the same, 0.19.24291. The strange Y axis behaviour I see is still the same. There is still the difference that you are running on Windows 10 and I'm running the AppImage on Linux.
On my system, the Variables icon for my AngleTest2 file hasn't changed - it's the same as the one you show for your AngleTest3.
I unzipped the AngleTest2 file and I see that the properties Animation Hints/Animation Hint List and Base/Expression Engine are both present in the file. They only appear in the Property pane if the Show all option is ticked (right click in the Property pane to see/change this).
Is it possible that you have Show all turned on for one document and not for the other? Another possibility is that these properties are only written to the file when it is saved, so if you hadn't saved your file after running Animate Assembly, they may not have been present.
heron wrote: ↑Tue May 18, 2021 12:34 pm
you did something that I do not understand.
I agree. I don't understand it either!
I've tried different ways of creating and attaching the LCS, but I always get the strange Y axis behaviour.
It would be very helpful if you could point me to the part of the manual which explains how you created your file. Perhaps you could also attach your AngleTest3 file so I can compare it against my efforts.
Thank you again for your help.