Files with CSW extension might be found as part of some ZX Spectrum emulators from RamSoft.
There is one other file type using
the CSW file extension!
.csw - Corel WordPerfect setup information data
What is csw file? How to open csw files?
The CSW file extension is also used for a compressed square wave format used by some older ZX Spectrum emulators, developed by RamSoft. Probably obsolete.
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