The OKBC Specification is hard to read. Any helpful hints ?

This depends for which purpose you have to use the OKBC specification.

For your first reading, read Chapter 1, 2,  Sections 3.1-3.5 and Chapter 4.  Before a detailed reading of  Chapter 3, it is best to have read the Chapter 4.

For an implementation-oriented reader, while reading Section 3.5, reading the source code for the default implementation of OKBC  operations (in files core*.lisp) can be useful.

Next: Do you have some references for background information ?
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