It should be that the printer firmware needs to be upgraded, and there will be a prompt when downloading the software.

^^^ this is most likely the issue--you need printer firmware version 4.4.x or better to read the new .ctb file compression algorithm...

I had to revert back to 1.7 in the mean time.  Once I get around to updating the printer, I'll update the results here.

How do you revert to previous versions if you don't have the installer? My new printer is a pretty much broken, until the manufacture comes out with a firmware release? No place to download old versions of pro? 

You can download previous version on this site, go to the Chitubox Basic DOWNLOAD page, scroll down to the bottom and click the Previous Versions link.

What printer do you have?

If it can read the older format .ctb sliced files it most likely uses a CBD-Tech (Chitu) motherboard and it is equally unlikely the manufacturer wrote the firmware. The .ctb formats are proprietry to CBD-Tech and manufacturers purchase motherboards and firmware from CBD-Tech. Are you certain there is no firmware update for your printer on the Chitubox firmware download page?

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