xml install erorr in theme

Hi!

I’m using Version 4.2 beta 2. I am trying to install the darkroom theme. I keep getting this error message

Sorry, there has been an error.
This does not appear to be a WXR file, missing/invalid WXR version number

When I follow the directions

Log into your site as an administrator.
2. Make sure you activated your new theme before proceeding.
3. Go to WP-ADMIN – Tools – Import
4. Choose “WordPress” from the list.
5. Upload the demo content .xml file included in the download pack.
6. You will be asked to map the authors in this export file to users on the blog.
For each author, you may choose to map to an existing user on the blog or to create a new user.
7. Please be patient while WordPress imports all the content. Posts, Pages, Projects, and Menus are imported.
You will need to assign the menu display locations & you’ll need to configure widgets.

I searched forums and called my host and none of the offered solutions worked. Here’s what’s been tried
1. Changing permission options
2. ftping it directly to he server
3. Host did not support me reducing the wp version then upgrading again after the file was uploaded or
4. inserting a line of code into the file to have it read as a wxr

Are there any other ways to update this file wpml-config.xml? Because I need it to configure all my content and menus.

Thank you in advance for your help.