I ran into a problem the other day trying to repair a process that had custom Reference Events.  Currently running BP 4.5 (4.10060.1.0).  It appears that if you download the current version of the process using either the K2 Management Console or Process Management Console in Visual Studio, the extra dll's necessary for the process to compile are missing. 

My workaround involved grabbing the original process out of our SubVersion repository and copying the missing dll's to the temporary internet folder that is used to temporarily download the process when using the Process Management Console. 

Does anyone know if this has been fixed in the latest update?