It has nothing to do with the agent.
We have over 10,000 Windows 8.1 systems monitored so far with the same agent, all working.
Here are some other reports from other software WITH the same issue:
http://answers.microsoft.com/en-us/windows/forum/windows8_1-performance/windows-81-pro-explorerexe-crashes-ntdlldll-module/e34b27fe-bf81-4347-a058-6441e96cd142?tab=question&status=AllReplies&status=AllReplies%2CAllReplies
http://community.avid.com/forums/p/123585/709660.aspx
http://omgili.com/thread/0xd.sZhj5je.krt0vaog619QWi3lsNohVBH0WDwHtzgjuFFBg6IbSRSCdWK_9ulQvox8Qy3TBLuIJOlz1BoyNcgis3VxzZRc/