> 2 - Dos versions? You'd be hard pressed to find anything running less than
> 3.1 and simple Dos programs would have no trouble with the later versions.

>               The serial com problems have been around a long time and the
> fixes/work arounds published.  Most of the problem today is in the
> variations in hardware.  Best to avoid serial and use the printer port.

For situations not needing high-throughput serial communications (and I
think a PIC programmer would qualify as such) it's possible to write
communications routines that'll work 'with anything' if you simply use
polled I/O rather than interrupts.  The one place this would be tricky is
that every byte of data sent to the PC has to be individually requested;
if that caveat is kept in mind, however, polled serial routines can run
effectively with practically no compatibility problems whatsoever.