I found some degree of work-around. Deleting and replacing the connectors seems to work. I hope I won't have to edit any of my old connections too much-this could cause some problems down the line.
Today I found the actual problem. I'm working in a rather large assembly- trying to attach to a lightweight component was the cause of the issue. By resolving the component I was able to make everything work as expected. Hope this can help someone.
The mode Large assembly is very efficente but impossible working editing Cpoint Route.