1. Some slowness can occur and it’s standard behavior since while you’re entering credentials, the script is being recorded as well
2. It’s pretty hard to say what happened without any additional info and also without seeing the whole script. If it was one time glitch, the OS could suffer with some system slow, as an assumption. If constant – you can send logs as it was mentioned in previos replies, our dev team will check it.
3. Generally, Scripting tool doesn’t support work with files due to security policy. You can send us complete sequence of steps (and, probably, your script) needed to be implemented so we can check if it is possible to do.