Hi Albert, are you able to post screen shots of one of the stored procedure definitions and the smartobject properties and methods?
I would suggest you contact K2 support as this may be a known issue when upgrading to 4.6.9.
Hi Albert, I can't see any issues with what you have posted. Have you refreshed your SQL service instance? Maybe also try creating a new smartobject based on one of those stored procedures and see if it has the same issue.
K2 Support team was able to figure out the solution. I just want to post it here, just in case if anyone is expiriencing the same issue. The problem was that during instalation of new version, the web.config setting ExecutionCulture was changed from "en-US" to "de-CH" (<add key="SmartObject.ExecutionCulture" value="de-CH" />). As soon as we changed this setting back to "en-US", the issue was fixed. Below is the link to the related aticle
http://help.k2.com/kb001458.aspx