I was having a problem I thought may have been a FileMaker 14 issues, but turned out to be more of a Windows 8 problem.
My copy and paste functionality was not working in any specify calculation dialog box, only on 14. This was happening on two separate machines. The original thread is here: https://community.filemaker.com/thread/84603?sr=inbox&ru=2994 but I thought this might deserve its own, as I could reasonably see this causing additional problems besides the one I encountered in the first place..
In most cases, the copy and paste would just not work, but on a few occasions, attempting to paste caused FMP to crash. Windows event viewer showed a system.outofmemory exception being thrown at the time of the crash. Examining this further, I discovered that often my resource monitor would be showing disk usage at 100%, even when the resource monitor was listing 0 MB/s across the board for the individual processes listed. I found this stack exchange thread on Google:
For whatever reason, it seems that upon installation of Windows 8, paging file size for virtual memory is only set to a fraction of the recommended amount. The article says 70%, however mine was more like 1/3 (1280 instead of recommended 3959) Changing this setting not only improved my PC's performance, but also alleviated the FileMaker copy/paste issue.
Several people from here as well as the FileMaker Forum tried to reproduce my problem, but were unable to, I assume only because all tried using Windows 7, where this seems to be more specifically a Windows 8 problem. Hopefully this post can help someone else avoid the inconveniences I was having.