Fantastic work, I don't know how you had the patience to mess around with all that. Good to be able to change things and have some idea what it will do.
Also, hmmm everything I read in the last few days (been awol for ages) suggested GTAIV v 220.127.116.11 (latest) could be modded without any kind of filecheck. Well, I was able to mod weapons and add new cars after I finally figured out how to edit the files (went straight from XP to 7, I am an administrator why am I continually asked to approve things!) but trying to get rid of the startup screen and change handling, the game still launched but nothing changed.
To cut a long story short, either the modified filelist.pak or Alexander Blade's File Check fix (I put both on at the same time) is still needed in 18.104.22.168 to get it modded properly. Sorry if everyone knew this, I haven't played the game in months and just spent several hours trying to get it working.