To return to a project simply re-open the project file in PS. Then, make your changes and, if you want the changed version to replace the original, simply save it; if you wish to retain the original alongside the revised version, use save as... and give the revised version a different name.
However, your thread title might suggest you are not saving your project prior to exporting it. Is that the case? If so, and you have closed PS without saving the project it is irrecoverable, sorry. Your only option in that scenario is to rebuild it. from scratch!
Did you save the project before exiting the program?
If so reload the project - it should be available in the Load project dialog
it may be named similar as shown above if you did not change the name on saving.
If not and there is not backup file called Autosave.MP_ in the folder specified in the program setting Paths tab then the project is lost and you would have to re-create it. - note: if you have created a different project since the one you wanrt to reload then the backup file will have been over written.
Thank you, gentlemen. I'll let you know how it works out for me. One more question. When I clicked on Back up copy, there are two options. (1) Copy project and media into folder. or (2) Copy slideshow and media into folder. What's the difference?
Use the first option - this is a full backup, it copies everything including any effects resources that are needed for the project and avoid potential issues with missing resources.
The Copy slideshow and media into folder is a slimmed down backup with no project file or effects resources.
One more question. When Exporting : Full HD or DVD Quality?
Entirely down to the intended method of displaying the final slideshow!
You just need to be aware, perhaps, that, contrary to a rather popular belief, "DVD Quality" is only ever Standard Definition; that is a mandatory part of the DVD specification. So, if you want to show your exported show at its "best" visual quality, choose "Full HD", but obviously you cannot burn such an export to DVD.
One other thought: on the screen where you see the options of Full HD and DVD Quality there are also other options, including 4K/UHD, though this may be "overkill" unless you have a 4K TV on which to show it.
On the "Burn" screen, you have the option to burn a DVD or a Blu-ray disc. The latter will give you the Full HD quality on a physical disc. (There is a third option on that Burn screen which gives you a HD burn to a DVD, so producing an AVCHD disc, but there is a limit of about 30 minutes to the playing time of your show and the disc can only be played in a Blu-ray player.) So many options!
My projects are not saving in Photostory Deluxe 2023. I have set the project to automatically save every minute and I hit the save button periodically plus ALWAYS hit the save button at the end of the day. I had experienced this a few days ago as well. Last night I hit the save button as usual but also hit "Save As" and put in a separate file. Almost none of the many changes I made yesterday have been saved. Any clues?