Lost your unsaved data?
Well, you've made a rookie mistake and there's no recovering from that. You'll have to redo your work. I can however offer a useful tip for unlocking the project that crashed so you don't have save it as another name and create folder after folder highlighting all of your mistakes.
Go into your project folder and delete the file that starts with:
Your file should now be unlocked. If you want to try this without deleting a precious file, change the extension to .BAK (backup) by simply typing .bak on the end of the file name.
Second helpful tip:
The project folder is for GoCAD's use. If you save over the now unlocked file with changes you've made since, GoCAD may spitefully delete any additional files you've put in this folder, including those lovely images of your model during construction that you agonized over.
Third helpful tip:
Many people get involved in their work and forget to save important changes. Set a timer on your desk or make sure you save your project every time you get another coffee, or interact with someone in the office. Backup your projects frequently, preferentially to an external drive that is nowhere near your desk or building.
These helpful tips were brought to you by the resignation of recreating the model I just lost, and the experience of dropping my primary drive and losing 3 months of un-backed up work.