I don't know how to access the photos I've taken, in the PSP verison you could just go into the XMB media tab and view them there. How do you do that on rpcs3?
Look in dev_hdd0/home/00000001/ if there's any photo folder. If there isn't, then that functionality is likely not working yet.
they are stored in hdd 1 cache but only the latest photo and only 1 at a time. how do I fix this?
Cache folder is exactly that, a cache. If permanent storage doesn't work, nothing you can do.