Can't access WP template files

I have a Wordpress theme installed that I have customized to some degree. The problem is I need to access the many template files associated with the theme while I'm designing pages, but the template pages are not showing up in the dashboard/page attributes.? I contacted the developer of the theme, and he suggested that either the Wordpress core is damaged, or a plugin is interfering with the template pages from showing up.? So I need a fix for this problem. I need to be able to access the theme's files, and if there is a problem with the wordpress core or a plugin that is in the way of this, it needs to be fixed right away. Please make a backup of the site if you are chosen. If anything goes wrong, I would like to be able to use a backup to mitigate any problems.? ## Deliverables 1) All deliverables will be considered "work made for hire" under U.S. Copyright law. Employer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the employer on the site per the worker's Worker Legal Agreement). 2) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 3) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Employer's environment--Deliverables must be installed by the Worker in ready-to-run condition in the Employer's environment. b) For all others including desktop software or software the employer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this project. ## Platform IE 8.0 Firefox 3.6 Safari 41