Even if your ps explains it, you could probably elaborate, give different examples, etc. I would not think it would be a good idea and copy and paste...but it would be alright to have the same ideas, just said in another way. (isn't your personal statement a little more "artsy" than the more straightforward, more cut and dry, answer they are seeking?).
And as for the activities...Its only logical that they asked you to input your activities for a reason. Maybe they don't download the activity description (UCSF says they don't on their website). Or maybe they like their secondary to be a standalone thing they give to interviewers. But whatever the reason, they know EVERYONE has their activities on the AMCAS, so if their secondary asked for it, they must want it there too.
If you don't fill comfortable, then just call them. You probably aren't the only one.