You have most likely placed a Tiff/Png File in your Project.This is just a warning that Files with transparency will look Opaque.Your Blurb Uploads will not be affected.
Reference Article:- Photos with Transparency in Lightroom : Blurb Support
I think panoramas created in LR (DNGs) will also show this warning, as they will have 'transparent' pixels about the edges that do not show in the cropped state.
"Transparency" has never affected any images in the books I have printed by Blurb.
Thank you for your assistance and yes I was able to confirm what you had stated.
I can confirm that the files from Merge do seem to be the cause.....
So I am not nuts!
For your info I was able to upload my book but I had to do it outside of LR. I had created a PDFs when I first completed the book but did this outside of LR. If I tried to generate it within LR I would get the same error message. Clearly there is a problem within LR that needs to be addressed.
Again thank you for your help.
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