Captivate 11.8.0.586 to Captivate 12.3.0.12

Hello, 
My company had created several eLearning courses using Adobe Captivate 2019 (11.8.0.586) and is looking to now translate these into different languages for our employees. However, they want me to update these already created files in the newer Adobe Captivate (the new version my work is using is 12.3.0.12). They're currently saved as .cptx files and I cannot get them to open in the new version as it only seems to accept .cpt.

Googling is failing me as I'm reading that it should be backwards compatible but, that doesn't appear to be the case from what I can see. Is there a way to open these files in the newer version? if there isn't a direct way to open these files, is there a way to convert them from .cptx to .cpt easily (hopefully without another paid software)? Am I doomed to redesign these training files in the new version?

Also, newer version.... is there no way to just create my own slide content without being restricted to these semi-template style content slides? I've only began to dabble with this new version but, it feels a bit limiting compared to how easily I could design in the 2019 version. I do see the option for "blank slide" but, for example, adding a photo I need to turn off captions and subtitles every time instead of just adding a photo... and if i want to move the photo around on the slide I have to change the padding from what I can tell. I was hoping for a bit more of a "freeform/drag and drop" option like 2019 where I could easily move things around without being as restricted as it feels. I understand that this is most likely due to the responsive design element and it's probably just a matter of getting used to it but, maybe there's a glaringly obvious checkbox or setting I'm missing somewhere? 

Please forgive my ignorance with these questions if they've been answered before (I've been searching the community but, not finding exactly what I'm trying to learn). eLearning is not my area of expertise and I am being volun-told that this is my new project, and that as a graphic designer, I should be able to easily figure this out. I'm off to watch a bunch of training videos to get up to speed on this new software 😞