Use adjective or adverb for clause + こと

Question

As I understand it, when you make a clause and then put こと at the end of it everything is transformed into a noun (e.g. 食べましたこと is eaten thing.) If it's a noun, it should be modified by an adjective, but I encountered this sentence

しかし、スケジュールの都合ですぐに公開することは難しく、断念せざるをえませんでした。

Source: https://www3.nhk.or.jp/news/special/international_news_navi/articles/feature/2023/08/01/33180.html

I'm not sure what to make of the 難しく. It isn't て-form so it must be an adverb, but wouldn't it be describing the noun スケジュールの都合ですぐに公開すること then? Or should 難しく be treated like it's part of the phrase before こと even though it's after everything?

I checked on https://senseijapanese.com/japanese-grammar/using-%E3%81%93%E3%81%A8-to-nominalize-a-verb-or-sentence/ and it gave

しごとのことがきらいです

as an example, so is it possible to use both adjectives and adverbs with こと?

Answer 1

こと is a nominalizer, and 食べたこと refers to the action of eating itself, not something that was eaten (food).

公開することは難しい。

Releasing (it) is difficult.
It's difficult to release it.

Here, 公開する is a verb ("to release"), and こと turns it into a noun, i.e., nominalizes it ("releasing").

Next, 難しく is indeed the ku-form of 難しい, but it's not used as an adverb here. It's used to join two clauses like a te-form does. This is called 中止法. The article you've linked has lots of 中止法 for verbs (始まり, 携わり, 退職し...), but the same happens with the 連用形 of adjectives, too. See: Use of く-form over くて in an い-adjective

With these two points in mind, the sentence can be parsed like so:

• 公開する
  to release it
• 公開すること
  releasing it
• 公開することは難しい。
  Releasing it is difficult.
• すぐに公開することは難しい。
  Releasing it immediately is difficult.
• すぐに公開することは難しく、...
  Releasing it immediately is difficult, (and...)
• しかし、スケジュールの都合ですぐに公開することは難しく、断念せざるをえませんでした。
  However, due to scheduling constraints, releasing it immediately was difficult, and she had no choice but to give up.

連用形 (aka "continuative form", or ku-form in the case of i-adjectives) is more than "adverbial form". See: Do I have a good grasp on the basics of what the continuative form is?