When you open a GameMaker document, GameMaker creates a temporary work file named "GMAKER.Temp". Any new sounds and graphics you create are added to this file. The original document is unchanged until you save it.
To open a saved document, you need at least as much available disk space as the document occupies. For example, if your document is 500K then you'll need another 500K of disk space for the temporary file. You will also need more space for adding new graphics and creating an application. GameMaker has problems when encountering a full disk, so a Hard drive with several Mb of free space is highly recommended.
If your computer crashes while GameMaker is running, the temporary file named "GMAKER.Temp" may not be deleted as it normally is when GameMaker quits. When GameMaker is launched again, it does not attempt to delete the file. Instead, it will create a new file (GMAKER.Temp 2, GMAKER.Temp 3, etc.). If GameMaker is not running and a temporary GameMaker file is on the disk, you may delete the file, but do not delete a temporary file while GameMaker is running.
