Thank you so much Nina! Everything was clarified by your comments,
except for a few lingering questions that I hope you don't mind if I ask:

If I were to translate "taking" as a present participle in this
sentence instead of a gerund, would "maala.m haranta.m" have been correct?

Also, I still don't really understand why the feminine singular
nominative was used (saalaa) rather than the singular accusative
[saala.m], which is what I would expect when going to a place.

Here's the sentence again: "maala.m aadaaya yena saalaa ten'
upasa.mkamimsu."

I realize now that yena and tena are used quite differently in Pali
than in Sanskrit! Poo.

Piya, yes, I'm glad that Pali study is available to those who want to
study the Dhamma. I myself am a PhD student in anthropology/religious
studies who studies Buddhism in the U.S., particularly among Sri
Lankan Americans. I actually have to pass a Pali language competency
exam, so I'm pretty motivated to understand the minutia of Pali
grammar, even if I stink at it!

Thank you again, and wishing you happiness,
Natalie