EQStitch is a PC program. It will only run on Macs that have been set up with Windows and optional emulation software (e.g. Parallels) allowing the running of PC programs on the Mac.
What about activation?
If you own EQStitch, as well as EQ7 for Mac, you can simultaneously run 2 activated copies of EQStitch on your PC (or Windows side of your Mac), and 2 activated copies of EQ7 for Mac on your Mac.