ssokolow: Please don't.
If you can post the information necessary to recreate the script, maybe one of us could do it for you. (I'd offer but, at the moment, I'm catching up to some backlogged coursework. However, if you remind me in July, I could.)
This is when I last updated the list
https://www.gog.com/forum/general/unofficial_dvd_covers_for_gog_com_games/post1450 The script parsed the posts from that thread and gathered the author's name, game names and urls.
Because the game names in that thread are the displayed game title instead of the game name that lgogdownloader uses, the script converted those by using data from GOGWiki and GOG game list.
When the script had gathered all the info it called a simple program that I wrote in C++ which modified the existing cover list.
Here's
add_cover.cpp which was used by the script to add covers to the cover list.
Compiling: g++ -std=c++11 -Wall -ltinyxml -o add_cover add_cover.cpp
Usage: ./add_cover covers.xml gamename author url
Maighstir: Now, I don't know how you currently check login status, but if you load
https://www.gog.com/userData.json, isLoggedIn will be true or false depending on said status.
That seems much simpler than what I'm currently doing.
Currently the downloader tries to find username or email in
https://www.gog.com/account/settings/personal and if that fails it tries to load
https://www.gog.com/account and checks that the response code is 200