All done. I reimplemented the substring decompression routine to another location (when each byte is read from the buffer) and now it works like a charm, allowing 1 byte of text to represent substrings up to 256 characters long. The best part is, the routine is incredibly more simplistic than before.

Here is the assembler code for those who care.

So the old, bloated, and time consuming substring modifications below have been thrown out, but at least I've become more comfortable with 6502 assembler and NES hardware.

In the screenshot, the strings retrieved from the substring table are represented by an arrow and the index number for now.



Again, thanks zooka :p