、。
After I compromised a bit, she agreed to the plan.
Literal
I [subject-が] somewhat compromise-and-after, she [topic-は] plan [to-に] agreed-[favor-くれた].
多少 ('a little, somewhat, to some extent') is a degree adverb. 譲歩する ('to compromise, to make concessions') is a formal noun+する verb. ~た後で ('after [verb]ing') marks temporal sequence. 合意する takes に for what is agreed to. The ~てくれる carries the nuance that her agreement benefitted the speaker.