Hi Evan! 
Yes, firstly you must run SetEscargotServer.reg (215 Bytes) file, but if you’ve alredy run it then everything is okay.
Make sure your account is in insecure mode (Old MSN Support), or you can’t even log in between MSN 1.0-MSN 4.7 versions.
You should try enable TLS, and disable SSL service. You can look more informations in Using Messenger with Escargot on Windows XP, and avoiding the 80048821 error
If still not working open this link: https://m1.escargot.log1p.xyz/ and you must get page not found (404) error. After that do a ping check to Escargot servers: Press Win+R keyboard shortcut, after that type cmd. type here ping m1.escargot.log1p.xyz . You must get back respond from it.
Lastly, I can say that use this Messenger file, I don’t know how it’ll work with Windows Messenger 4.6 so you should make a backup before you replace the files.
-Balázs