I battle-tested this script at Maker Faire NYC 2010 -- printing hundreds and hundreds of unicorns to be taken up eagerly by even the least likely candidates for receiving a unicorn drawing -- a real tribute to Will's logo design!
I have been using and loving the MakerBot Unicorn Pen Plotter for two months now -- am currently using the tool to create what is looking to be a rather involved animation project. One of the first adjustments I made to the python tool "Scribbles.py" (based on "Lunchlines" from the Frostruder project) was to jump into the included sub-scripts and adjust the pre- and post-print gcode commands in "context.py" so that the print cycle included a machine halt in a platform retrieval position before returning the pen to the ready-to-print position. After accomplishing this first step proved easy ("Scribbles.py" is quite hackable!), I added a few other neat helper tricks: disengaging the steppers before each dialog box for last minute fine-tune adjustments to position, a pre-print registration test (a dot to show where x0,y0 falls), a post-print musical riff (why not?), and an automatic height increment to drop 0.1 mm for each page peeled away from a sticky note pad. I used these tools together in the gcode included below to create an optimized, low-supervision-required print-to-pad version of the unicorn logo (below) that is an ideal early print for a new MakerBot Unicorn Pen Plotter owner. I'm also including the context.py file for your perusal. NOTE that the secret to this script is that if you agree to "Print the Next Sheet" an absolute position adjustment drops the pen tool 0.1mm to the next sheet down ... but while the pen is in the "up" position. And then each new page re-declares the current position to be x0, y0, z0 keeping all the math right for the next drawing. So this script takes the endless adjustment and guessing out of preparing to print so that the tool always starts and ends in the best position to print, with the height adjustment to make printing to a new sheet work without adjustment.
I suggest printing to a sticky-note pad that you prepare as a "sticky-note block." First, slide two strips of tape face down to trap the bottom 2-3 pages of the pad so that you can stick it down firmly to the platform without opening the pad wide enough to crack the glue. Then, take drafting tape (or even masking tape), firmly tape the three-non-glue sides of the pad down to the platform. Don't go all the way to the corners, just a 2-2.5inch piece in the middle if firmly stuck should be enough. I use a pen-top or a bone folder to make sure the tape is truly flush while I press the pad down to make sure it doesn't get skewed by the taping. It doesn't matter if the tape tears in the right-angle crease where the edges of the pages meet the platform at a 90 degree angle -- the bit that is along the edges of the pages is the important part. Now you should be able to remove a sheet at a time by taking your fingertip or nail to the bottom left corner and peeling across to the opposite corner. Go ahead and do a few test peels before you print everything to make sure you have the hang of it (and won't tear your pages).
Before printing the 10-page set, you can't be entirely sure whether the pen-tool is in the up or down position, so leave the pen point about 5mm above the printed sheet. When the dialog box pops up asking you to "Touch the pen tool of your MakerBot Unicorn to the pad" drop the pen down until it has good contact with the page. Giving it a little more play for gravity to press it against the page will ensure that markings are consistent across the surface of the sheet even if it is slightly slanted or lumpy.