The text in the top right corner kind of looks like 화로의 and 과오 though I'm not really sure.
Possibly translates to 'Fired' and 'Mistake'?

the text at the bottom contains the character 쌈 and a combination of what looks Korean characters ㅏ and ㅇ combined to form 강 or possibly 장 but with the Katakana letter ス (su) or Hangul letter Cieuc in place of the ㇷ like character. Also it looks like it has the characters 지음 in the top row and the characters 일러스트 in the bottom row.

So possibly 쌈장 지음 translates to "written by Ssamjang" and 쌈장 일러스트 may mean "illustrated by Ssamjang" though this is just a rough guess from typing stuff in to Google translate.

Bugbo said:

The text in the top right corner kind of looks like 화로의 and 과오 though I'm not really sure.
Possibly translates to 'Fired' and 'Mistake'?

the text at the bottom contains the character 쌈 and a combination of what looks Korean characters ㅏ and ㅇ combined to form 강 or possibly 장 but with the Katakana letter ス (su) or Hangul letter Cieuc in place of the ㇷ like character. Also it looks like it has the characters 지음 in the top row and the characters 일러스트 in the bottom row.

So possibly 쌈장 지음 translates to "written by Ssamjang" and 쌈장 일러스트 may mean "illustrated by Ssamjang" though this is just a rough guess from typing stuff in to Google translate.

you're right about 쌈장 지음 and 쌈장 일러스트.화로의 과호 is confusing to even korean like me.I think it roughly translated to "brazier's fault?" it dosent't make much sense in korean too.But then again,author says his intention is to give this fake lightnovel cover some hypothetical lightnovel-ish vibe.화로의 과오 does sound like name for some random chuunibou-like light novel in Korean.So that checks out.