Well, after bashing my head on the wall.. I managed to find the fix for the editor woes.
In editor.c, in both copy_buffer and copy_buffer_nohash, find the lines in the for loop that look like this:
mudstrlcat( buf, tmp, 100 );
in both, change it to:
mudstrlcat( buf, tmp, MSL );
Why? Well quite frankly it boggles me. The only thing I can figure is that it's limiting buf to 100 chars rather than strcat'ing the 100 chars from tmp to buf.
Oh yes, and to note: The editor DOES cut you off at 79 chars now, rather than 80. After some screwing around I've concluded that the fix is a tad more involved. First off, I don't quite understand why both the old editor.c and the one in 1.6 uses strlen(argument) > 79, yet the new one flags it as a long line while the old one didn't. Either way, even increasing this to 80 caused some issues. When going back into the buffer, it inserted a blank line. I think (and with more poking I can be sure) that this is also another issue of mis-matched integers. The only thing I'm curious about is why the sudden change...