*cache.lib doesn’t contain libraries - only a set of the specific footprints used by a particular PCB project. (*cache.lib is a human-readable, plain-text, file. Open it in “Notepad++” or your favorite text editor and look at it. By doing this you can’t avoid learning at least SOMETHING. Someplace on the kicad.org website there’s a document that explains the file syntax. Don’t be afraid to look inside other KiCAD files, as well.)
Have you looked for those libraries on the Olimex site? They may have made them available for folks like you who want to replicate their projects. If not, you could email Olimex and ask for the files. (Alerting Olimex to this Forum thread may help.)
I am still fumbling and struggling with the KiCAD library scheme myself. I think you can remove all those entries from the library table, leaving ONLY the *cache.lib file as a table entry, and KiCAD will find the footprints in cache.lib . (Get somebody else to verify that before you try it.)
A couple of weeks ago there was some discussion about compatibility between pcb files created from nightly builds, and files created from stable releases. I think this is the thread:
The culprit seems to be lines which refer to parameters for differential-pair routing. If the design doesn’t use differential pairs, you can remove the troublesome lines with a text editor and then the file is compatible.