Andrey,
As part of my collection of plugin functions, I was thinking of implementing an AutoSave feature. On occasions I typed something that SMath doesn't like and it will crash, losing work I spent some time on. The AutoSave would save a copy of the current worksheet contents to a temporary file in the Windows User Roaming directory. The .NET StopWatch is the perfect mechanism to save the worksheet every 10min or whatever the user wants. I was also thinking of an AutoRecovery that would open the last temporary file and the user could pick up from there.
I haven't been able to find it in the SMath dlls. Is there a way through plugin to cause the file to be saved and opened without user interaction. I was thinking of using the Windows temporary file name as the save as file name.