What error?

The Sage utility is the only recommended way to renumber / merge items. Even with SQL, there are things that cannot be scripted without major headaches.  I would never recommend direct SQL edits to anyone.

The utility can be slow, so do it in batches of 50-100.  Run a test and do the math.  I've had renumbering / merge requests cancelled due to the insane processing time required (what would amount to months, running 24/7).

Shoot, I thought I attached the screenshot.  The message said something to the effect of not finding a record in the IS_ItemActivation table.  Tried to pull the log to see if it said anything helpful.  Yes I read another one of your post and created a bunch of files with 50 products to import one at a time and merge them, just can't even get one product to pass.

Yes, that error is related to InSynch.  Contact ROI for assistance.