Help syncing LR between platforms?

I thought this was a very simple process since LR was a multi platform engine but I am finding out its not working very well at all.

I uploaded 1760 photos to LR from a wedding I did recently (onto Mac), exported as a catalog to a WD passport, imported that catalog to LR on my laptop (windows vista64) and edited all the images while on the road. No problems thus far....

I just tried to sync the catalog (metadata and develop settings only) back over to the Mac but it keeps recognizing only a little more than half of the images as existing on the Mac and starts re-adding these images to my catalog on Mac. Wierd part is that LR knows these are all duplicates because it stacks them all as they import and my catalog goes from 1760 images to 2760.

I really need to get this synced back over as the catalog went from one collection to 5 or 6 smart collections while working on the PC on the road and all my flags and color coding changed too!

Heres the workflow:

1. 1760 CR2 raw files from cards to Mac - catalog created
2. Catalog exported to WD passport drive
3. Catalog imported to LR on windows based laptop
4. Edits done, new folders created, flagging, rating etc.
5. Attempt sync catalog with Mac (File > Import from catalog > choose correct catalog > existing photos - metadata and develop settings only > import

Nothing.....no settings, flags, ratings, color coding, folders, collections transferred at all. Just adds duplicates to my Mac catalog even though I chose metadata and develop settings only.

What am I doing wrong? Its driving me insane!!! A little help please!

Do you have info leading you to believe that the LR catalogs are cross-platform? I'm asking because I haven't heard that and I don't work with both platforms.

What you should be able to do is, rather than re-import the images, save the metadata to xmp files on the one machine and read them on the other. You can pick up edit and keyword settings, but likely not flags, collections and such.

Multiple sources have led me to believe that catalogs are cross platform, as the application is designed not to care what OS you using. My most credible source for this is the Adobe support forum.

Ah, well, OK, maybe there are some here who are running it that way and can chip in -- hope you get it solved!

Thanks....me too. I worked around it for now. Exported the whole catalog, images and everything, to an ext HD then imported the whole thing into LR. Kinda worked, but I'd still like to be able to do it the proper way just importing the develop settings

Further research leads me to believe its the ext HD that may be the problem. Mac can't write to an NTFS drive, so maybe it cannot properly read and transfer info either? I don't know....I am perplexed. Everything else I read tells me I am doing everything right.