4DOS750B130.EXE - Rev. 7.50, full Windows installer. To extract under plain DOS use any DOS unzip utility. Rex made several minor corrections to this build without giving it a new build number. This is the current and probably final freeware version that Rex Conn gave to the public when dropping sales warranted no further commercial development of 4DOS.
4DOSHLP.ZIP - by Charles Dye, it is a variant (and more recent) release of the help file for 4DOS v7.50. To use it, rename your original 4DOS.HLP file as 4DOSHLP.BAK and then move this one into your 4DOS directory. 4DOS and the bulk of the help text are copyright JP Software; changes and new material in this file are by Charles Dye.