Duplicated Texture Files

Hi,
Have noted freezes at some add-on airports and suspect that this is due to the TEXTURE files duplication. Looks like often the add-on airport designers use the same texture files, which I already have in one of the libraries. Fo example the lates Islip KISP airport add-on uses small aircraft textures, which I alredy have in Static Object Library.
Is there any way I can clean these duplications without doing the micro surgery through all my files. The file find_all_duplicate_v2.4.zip, which is recommended is not available in either AVSIM or FLIGHTSIM.
And one more question please: What are the logistics of cross-referencing the libraries. For example if I want to use the Static Object Library textures at given airport, do I need to have any bgl in this airport scenery folder to point at these?
Many thanks for any help.
Peter