ywSynch works with Windows XP, Vista or Windows 7. It requires MS .NET 3.5 SP1 to be installed on the PC. This can be obtained from Microsoft here if the ywSynch installer finds that it is not already installed and is unable to install it itself.
You need a device (e.g. an Android tablet) to copy the yWriter project to. Ideally, the device will be mountable as a normal filesystem within Windows. If it isn't, and appears in Windows Explorer without a drive letter, you will have to use an sd card, USB stick, or something similar, to get files on and off the device. Alternatively, it is possible to have ywSynch write to a DropBox folder on the PC, and synch that with the device, or do something similar with any synch facilities that are built into the word processing app on the Android device.
You will also need LibreOffice and a Java Runtime Environment (JRE) installed on the PC to carry out document conversions if the editor on your device cannot edit and save rtf files. Both of these are free.