USFM3 includes some new markers for Ruby glosses (a special kind of annotation in Japanese), a new way of storing figures, and a few other new things. Details here

Versions of Paratext 8 before 8.0.100.76 (released May 2019) cannot read USFM3 projects. Recent updates to Paratext 8 can open these projects but the new markers might not display correctly. For instance, a figure inserted into a USFM3 project by Paratext 9 won’t be visible or editable in Paratext 8. You will see the info that a figure has been inserted but you will not see the figure in Preview or any other view. …  read more

There is no Mac OS version of Paratext. There are a variety of ways to create a virtual  machine running Windows or Linux, so Paratext for Windows or for Linux can be installed in that machine.  Please note that a virtual machine is treated just like any physical machine, in that you will need to purchase a Windows license from Microsoft in order to activate Windows on it.

• There is a free program called VirtualBox (http://www.virtualbox.org) that can create virtual machines.
• The commercial programs Parallels and VMWare Fusion also permit creating virtual machines. They are not free but may provide better integration with the MacOS and Windows.
• The Apple Bootcamp utility enables you to configure your Mac to boot either into Mac OS or Windows. You could possibly install Linux instead of Windows as your second OS but this probably requires some research and technical skill. This solution would not permit you to run Paratext and Mac programs at the same time like you could with a virtual machine.

If you have difficulties with setting up a virtual machine, look for the support options or information on the virtual machine tool you are using. Chances are your issue is a general virtual machine issue rather than an issue specific to Paratext. …  read more

The Convert Project tool will not work on a FAT32 drive. Since NTFS is the default file system for Windows since Windows 2000, your hard drive is probably NTFS unless it was deliberately configured to be FAT32. A USB drive is usually FAT32. To check your drive, go to Windows Explorer, right click on the drive icon and go to Properties.

On Linux: The Convert Project tool will run on a project stored on the ext4 file system (the default for Linux).