Hi. Thank you. Yes, I think those sentences I wrote weren't clear in content, that is what they meant. Let me introduce some sentences that seem to be clear in meaning.
He fell down as he was walking home.
He fell down as he walked home.
For the two sentences below, I moved the parts that come after the word "down" to the front of the sentences (like before
In this context, all 4 are OK, because the intent is clear. However, the 'as' clause (like a 'while' clause) usually requires the past progressive to make clear that its action is of a duration surrounding the relatively instantaneous action of the main clause. Therefore, in your examples, the ones with the progressive are preferable. The position of the clause is of no importance for meaning.