I am experiencing this same behavior with TestComplete 10 and Chrome 33. IE and Firefox work fine, but not Chrome.
TestObject.ClickItem text
Err.Number = 0
Err.Description = (blank)
Err.Source = (blank)
Log.ErrCount = +1
Error in Log: The drop-down box cannot be closed.
And the drop-down box IS left open by the call.
I'm not sure that packaging up the project and providing it will provide any help. This is a general-purpose SAFS library used for multiple applications with no TestObject mapping used in the project. However, we do have the TestComplete test log, the libraries used, and an extensive SAFS Debug Log. Info on how to get a more comprehensive TestComplete debug log might be helpful.