Did you allow Solidworks to run as long as it wanted to? It will give you an error if there are too many triangles for the STL file.
Regarding 4 different STL files, there is nothing that you can do for merging them with Solidworks, but maybe your printer has some capability like that?
I have waited for 1/2 hr+ for SW to successfully save out STL files.......
The first thing I would try is to try some custom settings in the STL options before you export, to see if you can get the triangles down to something like 6 million. In my experience, SolidWorks will consistently save an STL at this size.
Occasionally I have been able to save larger files, at the expense of waiting a longer time, but have often had SolidWorks just hang as you have described with very large files.
I usually leave the "Preview" box unchecked in case the mesh generation is the reason for the hanging.
I have the "Show STL info before saving" box checked. Usually this message always comes up just before the file is written, so you will get this info even if it hangs, or is unable to save the file.
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