This is a list of files needed by PhotoPost for normal operation:

data/*
forums/*
help/*
images/*
languages/*
stylesheets/*
templates/*
uploads/*

adm-cats.php
adm-inc.php
adm-index.php
adm-misc.php
adm-photo.php
adm-users.php
bulkupload.php
comments.php
config-inc.php
config-int.php
ecard.php
editphoto.php
header-inc.php
image-inc.php
inc_features.php
inc_photopost.php
index.php
member.php
misc.php
pclzip.inc.php
pp-inc.php
register.php
search.php
showfull.php
showgallery.php
showmembers.php
showphoto.php
slideshow.php 
uploadphoto.php
useralbums.php
watermark.php

The following files are only needed during the install or upgrade process and should be removed when you have finished:

CHANGELOG.TXT
install.php

UPGRADE.TXT
upgrade.php

and, of course, this file filelist.txt and CHANGELOG.TXT files do not need to be uploaded.