AGP
There can be a problem when NaTKiT1 is run on a machine using a AGP display board.   The symptom is a "Chinese writing" screen like the one on the left.

The problem first manifested running the  simulation version (NK1_SIM.EXE) in a window under NT.  (As it says on page 4 of the user guide NaTKiT1 shouldn't be run under Windows.  The NaTKiT will run slower and errors may occur because it does not have guaranteed access to the PC’s resources.  In fact we only support  NaTKiT1 if it's running under DOS.)  Recently the problem has also occurred under DOS.

We suspect that those nice people who write drivers haven't maintained full DOS inheritance ... and it has to be said that so far this problem has only occurred on Dell PCs.

Fixes that have been used are: 

• see if there is a more recent version of the graphics driver software,
• make sure you have 
  MODE CON CODEPAGE PREPARE=((437) C:\DOS\EGA.CPI)
  MODE CON CODEPAGE SELECT=437
  in AUTOEXEC.BAT, and
  DEVICE=C:\DOS\DISPLAY.SYS CON=(EGA,,1)
  in CONFIG.SYS
• if you are using DOS v6.22 downgrade to v6.20 - no it doesn't make sense to us either but it worked for Sunil,
• replace the AGP display board with an ISA or PCI board,
• don't use Dell PCs,
• wait for NaTKiT for Windows.

Thanks to Sunil Mathur at B&W Loudspeakers for helping to identifying this one.

Y2K
One user (Martin Audio) has one PC which when tested rolled over to Jan 1 2084.  They discovered if the date is greater than 31 December 2078 then NaTKiT ends with the error message "Illegal function call in module NK_LREL at address XXXX:XXXX".  One to watch out for.