Past Tense – Using ‘Was Working’ or ‘Worked’ for Events in the 1990s

Both versions are 100% grammatically and idiomatically correct. They have nearly identical meanings, but offer slightly different opportunities for usage.

Miguel came to the presentation but he seemed very distracted and he did not listen to anything that the speaker said.

In this sentence, the presentation is over and we know that Miguel never paid attention.

Miguel came to the presentation but he seemed very distracted and he was not listening to anything that the speaker said.

There are two possibilities for this sentence.

1. Alone it means exactly the same as the "did not listen" version.
2. With some additional description of his behavior, it describes Miguel's ongoing actions during the meeting, but offers the possibility that they were interrupted at some point.

Miguel came to the presentation but he seemed very distracted and he was not listening to anything that the speaker said. However, the speaker was so skillful a lecturer that soon he was as captivated as the rest of the audience.

We would use this second version to tell the story of Miguel at the presentation if that story was more involved than "He didn't listen."

Two examples:

She isn't as friendly as I thought.

She isn't as friendly as I was thinking.

I think both of these examples are gramatically correct depending on the context. In your first example, "I thought" refers to your thinking which existed in the past but doesn't exist in the present moment. In the same way, In your second example, 'I was thinking' also refers to your past-thinking but It's in continueous form. It means you were thinking in the past that she was friendly.

Both of examples could be understood as follows:

She isn't as friendly as I thought she was friendly.

She isn't as friendly as I was thinking she was friendly.

What I think the difference between these two examples is- In the first example, 'I thought' refers to simple past Tense and in the second example 'I was thinking' refers to past continueous Tense.