Best practises for creating a little image gallery ...

[eluser]CARP[/eluser]
Hi CI people
I'm about to begin a little backend for managing an image gallery
I've been searching in the user_guide, but could not find a file management helper or something similar

- Should I use the standard php functions for creating folders and set permissions for each sub-gallery, or should I use some std. CI lib? (which?)

- Where should I store the images, data, thumbnails, etc. for each gallery? Inside 'system'?, inside 'application'?

EDIT1: regarding user_guide's example for creating thumbnails, should I load the image_lib library inside the for(; loop for batch thumb creation? I say this because I'd need to change $config['source_image'] in each for loop and load the lib again... not optimum, right?

Thanks a lot in advance,