To rule out Visual Builder, you can direct users to turn off Visual Builder for printing -
1. Start Business Manager
2. From the menu select Company|Preferences|Form Settings
3. Untick Enable Distributed Printing and press Save
This will at least rule out the possibility that the way they are using Visual Builder is creating problems.
If you, however, now find that Business Manager begins to freeze or lock intermittently, then that would make me strongly suspicious that there is an issue with a print driver. Print drivers tend to be a fairly common source of network and local instability.
Sometimes, when it takes a long time to connect to a printer across a network, even this can create problems. Users get impatient and click on the software multiple times. Windows detects that the software is unable to respond immediately, and invokes a white screen do-you-want-to-shut-down-the-app message, and that message can itself cause a running application to fail.
If an app is unable to shut down cleanly, parts of it can remain in memory as a process.
Unfortunately if the issue is intermittent instability there could be a dozen other potential reasons why apps are dying when accessed across a network connection. But because VB is implicated my first suspicion would print drivers, since they are such a common source of issues.