Can the latest version open files created in older versions of KaleidaGraph?
As long as the files are intact, the current version can always open files created in older versions of KaleidaGraph.
Files created in v3.6 can be opened in v3.5, and vice versa. Version 4.5 allows you to save plot and layout files in a v4.0 or v3.5 format. The data files can be saved in a v3.5 format (the file formats did not change from v4.0/v4.1 to v4.5).