I tried cutting and pasting an Earth Elemental today (from Conjure Elemental p123) and the 'OK' button wouldn't accept the write-up. I had to go in and build it manually.
The same thing happened with Elder Elemental from the bestiary, but it did accept other cut and pastes fine. I couldn't figure out what was different about those ones specifically.
I have an identical issue, but with the "Dog" entries. None of the three stock dogs will parse through the builder. Is there perhaps a small but important formatting difference in some of the book statblocks? If there is, I can't find it.
Both of these issues are now fixed. For those interested, the problem in the stat blocks was a missing footprint and/or reach. The NPC builder was also having trouble with 'Treasure: none', this confused its poor little mind.
Also, some may like to know I've also just added a new feature, the 'Explain XP' button which sits next to the threat level drop-down. Clicking this button will show a complete point-by-point breakdown of how the XP total for the NPC was reached. It should be useful for fine-tuning an NPC to a target XP total, and also for diagnosing the occasions where the total on the builder differs from that in the book.
If anyone does find a problem in the XP calculation please let me know here or via a PM.