Questions about the Forgotten Realms Underdark

I am starting a 5E D&D campaign set in Menzoberranzan and its environs and I had a couple of questions for the FR gurus out there.



I used to have a PDF of Skullport that I got LEGALLY for free from the old WOTC website. Is it archived anywhere or do I have to buy it from the DTRPG website?



I have seen an image of a 2-page map of the FR Underdark on the web but I don't know what supplement it is from. Is it in the 3.5 Underdark book or somewhere else?



Thanks for any info on the above!

Questions about the Forgotten Realms Underdark