I also have a package that inexplicably hangs (on 64 bit server). It hangs intermittently even in the designer. My package is simple, with one dataflow that reads data from several sql tables and updates several other tables. I have only been able to catch it hanging in the designer when there is no data in the pipeline. So if one of my data sources has no rows and I try to do a merge joins with data from another table, it might hang as if waiting for input. Since this condition happens a lot, my partial workaround is to check the rowcount on the tables before executing the dataflow and not execute it if there is now data to prevent it from hanging. Even this apparently doesn't always work, but I haven't been able to catch this type of failure in the desginer.
If no one knows how to solve this, perhaps someone knows how to have a package timeout. If I could get the package to timeout or fail, then I could re-run it and possibly get it to succeed. As it is I have to manually go in an stop the scheduled job that is stuck and restart it.
Any advice might be helpful. Thanks.