well i've got a serial interface, but as far as i can find, the only software available for atari to pofo over serial interface involves using the document print command over a null modem cable... (http://www.atari-portfolio.co.uk
)...so therefore you can only transfer things in one direction. The software at the link you posted is in german...so not 100% comprehensible to me! As far as i could work out the serial program can transfer over a standard ST serial port or a TT's second serial port....is this the same as a falcon's second serial port? I've tried looking for details of this but so far have been unsucessful.
Otherwise may be a case of writing the software for myself! Would be great to have a program that could synchronise the portfolio's diary with a diary on the atari in the way that psions/pocket pc's do. Anyone else interested in something like that? Couldn't start it til the summer at least though...too much uni work in the way!