Pause script execution until file exists

I am trying to pause execution of a script until a file has been created (by a plug in that doesn't send a notification that it has finished), so that I can copy the file to another location before it gets overwritten by the next one. All this needs to take place without any user intervention. I have tried using the timer control, but as it's a control rather than a function I don't think it's possible to use it in this situation (the documentation is a bit sparse and a search of the net has not brought up anything useful).

My questions are:

is it possible to pause and resume execution of a maxscript? and if so, how is it done?

is this a job for .NET? I have some experience with C# so would not be averse to going down this route. Are there any tutorials on using .NET for this type of thing?

If anyone has any ideas as to how this could be achieved I would be very interested in hearing them.

Thanks in advance...