1) The Orbit microcode occasionally expects to be able to do a double-word read in cycles 6 and 7 instead of the usual 5 and 6.
2) The double-word logic incorrectly handles several species of overlapped read/writes, which Spruce's layout microcode uses.
As a result, Spruce now works, as do the Smalltalk-80 images.
Several tweaks to microcode disassembly (still rough).
Completed Orbit / Dover ROS / Dover Print Engine emulation. Still some rough edges; it works and can create PDF output.
Tweaked Disk Controller's Restore operation, it is now more accurate though wasn't causing any noticable issues.
