1) The Commissar Knuckles's Hat section is a parody of a ongoing thing in Czech kid magazines, where there's some kind of a detective and friends, solving a "crime", and you have to answer riddles and stuff to find out who of the four suspects isn't the culprit.
The first and only task here, eating porkchops, believe it or not, came from the Whale Rider. That's a consequence of "flesh" and "meat" being the same word in Czech, "maso". So when Koro teaches the Maori boys about sticking their tongues, being a warning to their enemies meaning "I'll eat your flesh", a Czech viewer can basically translate that as "I'll eat your lunch" instead, and when we were little we probably didn't want to think about tribal warriors threatening to eat their enemies, so instead we though of it as Maori eating porkchops.
Don't think too hard about it, some of the household lore has very strange and convoluted origins.
2) The fact that Commander Keen drank water on the fifth platform is a reference to Czech song,
Pijte vodu (Drink water), where something similar occurred in the first verse.
3) The character of Mates is based on a Czech kid actor, Jan Vokrouhlecký, more precise on his role in a TV show about kid safety. He said the line with the lemonade when about to drink pear spirit. It probably hasn't such humorous impact in English as it has in Czech, where he says "limonádička", a diminutive of "lemonade", so it's even funnier. The purpose here was to hint that Commander Keen drank some sort of booze. Blowing up something with candy is another thing he did in the show.
4) Committee, Senate, and Mekbakers are all part of family lore, and I can't give them much justice with words. Can't really explain.
5) Sam Woodyard speaking is a line from Catweazle, old British comedy show. If you don't know it, definitely give it a watch, you won't be disappointed. "But I'll find it out" is another line from there.
6) Pepa is basically Pepa Smolík (Géza Mezgá in original) from the Hungarian Mezgá family series, another shows I recommend you to watch, though they probably don't have english translation. Anton is Antoine from Sonic, Gerolt is Geralt of Rivia, Ewowa is Elora the Faun and Long Johnny Barbecue is John Silver, nothing too complicated there.
7) The line "Just gimme a lil' signature 'ere, chief." (Tady se mi prosim upište, šefe), is a line from some Czech commercial.
Lots of these aren't necessarily funny on their own, but as I've said, they're sort of memes in the household, they're recognizable to us and this comic was written directly for my sister. Hope you found it at least a bit interesting.