During the project numerous problems were encountered. Some were
solved. A lot of problems were caused by trying to stretch
software much: 
had problems with all the automatically generated links,
created to link together more than thousand different screens. Maple
and Mathematica turned out to be a little rigid in interactive use:
MapleV3 for Unix doesn't accept arguments on the command line
which makes it impossible to start a Maple worksheet from without
an other application. Most X applications, for example
Mathematica are not controllable via Remote Control.
Good exceptions form Netscape for X and Mosaic for X, enabling
it to load a URL in an already active Netscape window, say,
via following a link in for example XHDVI. In the Mathematica case
for example this is not possible:
every time time a link to a Mathematica Notebook
is followed, a new Mathematica front-end will be started. This will take
time and will fill the screen of the user gradually.
After writing some extra scripts the way from to PDF was
in the end more or less automatized, though
fonts had to be bought to be able to create
readable PDF. Meanwhile free fonts are available, please read the
hypertex homepage for more details, see [3]. Tcl/Tk
is supposed to be system independent, but the 
version that was used
for Dos-Windows was not able to work with the code written for
Unix in a correct way.
At the end of the year students had a first look at the Dos Windows version.
They were enthusiastic. Meanwhile, the project is continuing, using
some new techniques like JAVA that can help to make the interactive
book more compact and integrated.
RSA
Riaca's Interactive Algebra
References