I got a bug report (https://mods.factorio.com/mod/ModuleInserterEx/discussion/67743fff1c4d7b0e4bba85ed) that was caused by both our mods using the same name "window" for a gui element in the players main screen. Since that location is shared with all other mods, and gui child names must be unique, using a generic name like "window" should be avoided because of the potential for conflicts like this. I updated mine to be prefixed with the mod name - you should update yours as well (another option would be to not give it a name, and instead store a direct reference to the element).
