Would getting stuck on one block (not following the chain anymore) indicate a flaw in the build I'm using, something going wrong on my computer/connection or with Primecoin in general? This has occurred 3 times today, but not once before that. The issue happens long after I started mining, anywhere between 1 and 5 hours after startup. I have been using the following builds and had this happening with both builds:

Generic Windows client based on Chemisists improvements, compiled by fabrizziop
https://bitcointalk.org/index.php?topic=253662.msg2716037#msg2716037

Release 16 Windows client optimized for SB i5, by Zalfrin
https://bitcointalk.org/index.php?topic=253662.msg2711432#msg2711432