ProDOS disks originally formatted on an Apple IIgs and then inserted into an AV Series Macintosh running Apple File Exchange 7.0 can take up to two or three minutes before the contents of the disk are displayed in the right side window of Apple File Exchange.
However, upon inserting a ProDOS disk Apple File Exchange does not indicate that any activity is taking place. For example, the cursor doesn't change into a watch, menus don't respond, or the floppy is accessed intermittently resulting in the appearance that the Macintosh might have frozen or crashed. Once the ProDOS disk contents are displayed however, complete functionality is restored to the Macintosh.
Therefore, Apple recommends patience when attempting to read ProDOS disks when using Apple File Exchange 7.0. Subsitiuting Macintosh PC Exchange version 2.0 or later for Apple File Exchange is a good alternative to waiting for Apple File Exchange, since Macintosh PC Exchange does recognize ProDOS disk formats. However, any version of PC Exchange prior to 2.0 will not work.
Another work around is connect the Apple IIgs to the Centris 660AV using an AppleTalk network and transferring any ProDOS files to the AV Series Macintosh using System 7.x File Sharing.