I reported this to Bluebeam Tech Support as a bug. They didn't really seem to think it was as much a bug as just a slow network connection on our part.
When working on documents on our server, when I go to insert a page into another document, when you click the ADD button and the Explorer window that opens has the preview pane turned on, and you select the document you want to insert and hit OPEN before the document completely draws in the preview pane, the Explorer window closes but the inserted document does NOT appear in the Insert Pages dialogue list. The fix is to either wait a couple seconds for the preview to draw OR to turn off the preview pane. This problem does not happen if the files are local - hence the thought that it is the slower network connection (slower than being local) that causes the problem.
From the log files (see below) it does seem that it is the fact that the preview pane doesn't finish drawing that causes the problem. Regardless, I still think it's a bug.
Error : 09:13:12 : Exception Invoke or BeginInvoke cannot be called on a control until the window handle has been created.
System.InvalidOperationException: Invoke or BeginInvoke cannot be called on a control until the window handle has been created.
at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous)
at System.Windows.Forms.Control.BeginInvoke(Delegate method, Object[] args)
at Bluebeam.Framework.Dependencies.WinMainThreadInvoker.BeginInvoke(Delegate pDelegate, Object[] pArgs)
at Bluebeam.Framework.Redline.DoAnnotationsLoaded(Document pDocument)
at Bluebeam.Framework.Support.Annotations.AnnotationManager.a(Object A_0)
