Basically like ね, but more so.
～ちゃう is an abbreviation of ～てしまう, which in this case is adding a sense of regret to the sentence. “I’ll become fat (and that’s a bad thing)”. Please note that the いると is part of the clause above.
It’s 行こ― = 行こう, and yeah, plain-form volitional. “Let’s go”.
It’s passive form. 癒す = it heals (people). 癒される = (people) are healed by it.
It’s an alternative to the て-form.
… There’s an English version? But yeah, I think I might have gone with “That’s because it’s in the magazine too” perhaps?
“That being said” works too.
It’s おいしそー = おいしそう = “looks delicious”. Don’t lose track of those vowel elongation marks.
Yeah, it’s ～ていた. You’ve already seen ～ている abbreviated to ～てる several times this chapter. 
It’s もん = もの drawn out. “The reason is because…”
歩けば = if I walk
それなり = in itself; as it is
Think the translation is heavily based on what’s going on in the panel - the idea I’m getting is “because I live in this enormous house, just walking here (even though I live next door) is an adventure in and of itself.” Sort of thing.
Yeah, the vocab list seems miss all of the aside comments. If memory serves, someone generated the list off a script, and I guess the aside comments are missing from that script. I added most of them as I saw fit - didn’t really see the need to add the ones from this panel (though I guess キャッチ＆リリース could have done with more explanation).
It’s in the “bis” version, not the original.