It seems to work fine without any buffer needed, I'm running compiled from master and it's good.

Printographer works once you RUN CONFIGURE to set the printer and parallel card to Grappler Plus.
Zoom Grafix 10/83 (zgfx1083) works with Grappler as the printer card.

Listing basic programs with PR#1 and LIST works as well. (If you want 80 columns, do a PR#3 first). You don't have to worry about the high bit problem, which is cool.

And if you enable the ap2000's keyboard, you can change fonts on the fly with 7 (NLQ roman/sans) 9 (draft) 1 (compressed only works with draft).
(While it's printing hold it down until it gets to the end of the line and waits until you release the key).