The library seems very good, no need installation, only using unit, in this case synaser.pas. The project is open source and well organized.
With the sample project we connected an Arduino that is a very cheap microcontroller.
Some example of using Synapse Library can be found on http://wiki.freepascal.org/Hardware_Access .
the program that read and write to usb as a serial port:
the piece of code that use synaser.pas :
hoping that is interesting