Start Part 1 - Download csv, Upload Images, Ignore Categories
When you first log into STCtoCart you will see a table of the current settings, assuming you've already installed the required 3rd party module at the requirements. In addition you'll see that most buttons and web pages have an 
image that hovering over will give additonal infromation about the button or form. Now most users will want to get started right away, so the settings on the Home page can be ignored for now. To get started click Options > Manual Update, you'll see various form buttons each with a specific function and order of precedence.
NOTE: If you've installed sample data into Magento or have created test accounts and orders. You should first open Options > Fresh Database to remove all of this information and start with a new Magento database. Why this option is not available inside the back office I don't know.
1. Download xxx.csv
2. Upload Images
The 1st button will download your chosen data feed and put that information into a database table for easy access. It also makes some slight modifications to the original data feed categories so their is no conflict of having two named the same. This whole process takes approximately 15 to 20 seconds depending on your current server load and distance from SexToyClub servers located in Chicago.
The 2nd button download all images that are in the data feed, including extra images if a product has them. It will rename all images to the product number for easy identification. This initial download of all images is to have them available for Magento's import engine which requires the images alread be on your server for processing. This whole process takes approximately 1 hour to download the 15,000 plus images in the stc-02.csv feed. Again the time frame is affected by distance and your server load.
NOTE: The Upload Images will only copy images that are not already in your Magento product data base.
After the above is done, it would be wise to open Options > Ignore Categories and add any category that you don't want to sell from. Hovering over the image will show in the box a link to all current categories listed in the data feed you just uploaded above. See the pop-up information box for how this works.
If there are specifc products you want to ignore, be sure to add them in Options > Ignore Products before trying to use the Create Import CSV button!
3. Create Import CSV
This 3rd button is what creates the new csv file needed by Magento to upload all information. The script that creates the new feed will ignore category names and products you specifiy in the Options > Ignore Categories and Ignore Products web forms. Because of the time to run a brand new install, it's best to make sure you've done the above ahead of time. A little time spent browsing through STC products and categories will save you from having to start all over.
In addition the Create Import CSV button will create a feed with or without attributes, the attributes that are provided in the feeds do not affect the price of the product and should be shown only as text options. However Magento doesn't allow only text for the options, if you want to show the options in Magento. You need to select which format you wish to show Multiple or Checkbox. You can select which one you want on the Home page of STCtoMag. See the images below for an example of how they will look:
Multiple:
Checkbox:
Procedures for using the newly created import feed:
After the Create Import CSV button is pressed and done creating the new Import feed you'll need to press the Back Office link and navigate to:
System :: Import/Export :: Data Flow Profiles :: Import All Products :: Run Profile :: Select All_products.csv :: Run Profile in Popup.
For the first run even on a dedicated server putting 15K products into Magento database can take 10 to 12 hours with the way their Import software and the data base is designed.
Be prepared to start over too, the biggest chunk completed on my server without timing out was roughly 7000 items. Whenever the Magento import engine times out, just run this button again to start over. You'll also have to start over in the Back Office, otherwise it won't recognize that you have a new Import feed. If I have to create a new Import CSV file, I like to check that the System :: Cache Management :: has not problems before going back to Import / Export area.
When the Import CSV file is create it will only have products that are not already in Magento data base!
NOTE: When STCtoMag is in "Update Only Mode" this button will only add products to existing categories and instead of using Category Names, it uses existing Category ID's in the database.
NEXT....