I will email the project file today. Thanks for looking into this!
I could not duplicate the issue with a debug build of the Production version 2.9.2. R16 was already replaced with R0, so I tried R0 -> R16 (opposite). It worked fine. I tried it with the various documentation options (Move, Copy, Nothing). With the Doc Editor opened. I tried it Online with one of my PLCs, with status ON - sometimes Status adjustments to project changes is what causes issues, not the actual "Replace" function. I could not duplicate it.
I tried it with a larger project that has a ton of documentation where the existing Doc Editor Paste issue exists, with the Doc Editor opened. I could not duplicate it.
Can you duplicate the issue with the project you emailed us (rename it and do it on that dummy copy)? If you can, provide the specific detailed steps you took to get it to "hang". It's difficult to fix a problem that we cannot duplicate. Trust me, there IS an issue there - software does exactly what you tell it to do. If we knew the "magic steps", that almost always isolates it enough we can figure out what the bug is.
However, don't spend too much time on this - I know you need to get YOUR REAL WORK done. Sadly, it may rear its ugly head without you even trying (but may provide more/different details).
Oh, remember to Save Early, Save Often. :-D