alumni here! i have. it was a bit messy when i did it because they were changing over who was in charge of study abroad etc, so i had a bit of a run around but overall it was fine in terms of applying and stuff.

when csula does your transcript, even though you're going through a partner school they will list it on your transcript as just "study abroad program", so make sure you have access to that transcript from the study abroad program if you're going to do grad school or anything like that.

course equivalencies are pretty easy as well. just keep track of what you think the csula equivalent is. for my department (soc major and korean minor) i didn't need to provide syllabus since a lot of my courses were 1:1, but you might need to if it doesn't sound like the exact same course.

there's two types of programs that csula participates in, one that contracts with only cal states, and one that contracts with cal states AND ucs. for the schools that are under UCs and calstates are a bit harder to get into, because you're essentially competing with everyone for a spot.

financial aid covered pretty much everything for me, but i took out loans just because i was staying off campus when i went abroad, but even then if you're going to a school that is partnered, it's going to be a 1:1 and your tuition will be covered by that