Disk Image Preferences

You can access the Disk Image Preferences by selecting "Preferences..." from the "Edit" menu, and then clicking on the "Disk Images" tab.

General

If "confirm disk image format" is enabled, you will be shown the Disk Image Characteristics dialog whenever a disk image is opened.  This gives you an opportunity to see what format CiderPress believes the disk is in, and to override it.

The "default to read-only when opening volumes" setting determines whether the "read-only" box is checked in the Open Volume dialog.  This should normally be set as a safety feature, but if you find yourself writing to physical disks frequently, you can save yourself a click by disabling this option.

"Allow write access to physical disk 0" disabled a safety feature.  On most systems, physical disk 0 is your boot disk (i.e. C:\).  If you have multiple drives, this may not be the case.  By default, CiderPress prevents you from opening physical disk 0 for writing; if you set this checkbox, write access will be allowed.  It's best to leave this disabled unless you get a message that says, "Unable to open '80:\': for safety, write access to this volume is forbidden" while trying to open a disk that you are sure contains Apple II data.

ProDOS

When Apple released GS/OS, they added the ability to have lower-case letters and spaces in file and volume names.  This made file listings nicer to look at, but broke compatibility with versions of ProDOS 8 older than v1.8.  If "allow lower-case letters and spaces in filenames" is enabled, files added to ProDOS disks will use mixed-case filenames.  If disabled, all filenames are stored in upper case.  Uncheck this item for best compatibility.

The "use 'sparse' allocation for empty blocks" option enables a handy space-saving feature.  Disk blocks filled entirely with zeroes aren't actually written to disk.  Every version of ProDOS supports this feature, so there's no real reason to disable it, but it's there if you want to experiment.