Once you have → downloaded RealFlow 201610, extract the archive and open the disk image:
Drag the "RealFlow 201610" icon onto the "Applications" link to install the program.
Go to the "Applications" of your computer, search for "RealFlow 201610" and attach the application to your dock or open it directly.
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When you start the application you will be asked to → license your copy of RealFlow 201610.