GOG Galaxy is way too strict on which games are allowed to be manually added to our libraries. There appears to be an allowlist that filters around 10% of itch.io games. This defeats the entire purpose of having a "manual" add game feature.

One particularly egregious example of this is east van EP, which is distributed as three separate executables. There is no way to add all three of these at once to a GOG Galaxy library. You are forced to enter simply "east van EP" and link only one of these at a time.