I'm happy to share the internals of the .msb file structure with you if you want to develop that tool further. It's not too complicated. I'll send you a PM with the details if you would like.
As far as why I didn't just use the ZIP file format, my concern was the loss in speed due to compression and any other overhead due to the zip file specification. In my testing, compressing PDFs and image files does very little, so I didn't want the backup/restore process to be slower for no gain. I realize now that this was probably unnecessary, as it is possible to use zip files with no compression. I just looked at zip4j, and it seems like this would make it pretty easy to create a backup file in a zip file format. I think I will add this as an enhancement - the choice to back up to a zip file or msb file. I could also then offer the ability to compress for those that want it.
Mike
As far as why I didn't just use the ZIP file format, my concern was the loss in speed due to compression and any other overhead due to the zip file specification. In my testing, compressing PDFs and image files does very little, so I didn't want the backup/restore process to be slower for no gain. I realize now that this was probably unnecessary, as it is possible to use zip files with no compression. I just looked at zip4j, and it seems like this would make it pretty easy to create a backup file in a zip file format. I think I will add this as an enhancement - the choice to back up to a zip file or msb file. I could also then offer the ability to compress for those that want it.
Mike