An on-line video tutorial is available at:
www.softinterface.com/Convert-PDF-To-Image/Documentation/Default.htm
The user interface was made to allow for both simple and complex file conversion tasks. 'Convert PDF To Image' can convert a single or whole folders of PDF files. For a successful file conversion, do the following steps.

For every conversion job, you will need to do the following 4 steps:
(1) Select Convert Files as the action to do.
(2) Select the file or folder format from the Input File Type drop down list, then enter the path to that file or folder in the Input File(s) text box.
(3) Select the format the file or folder is to be converted into from the Output File Type dropdown list then enter a full path to place the converted file(s)/folder. If a destination folder doesn’t exist, CPTI can create it for you although you.
(4) Optional: If you are going to specify more than one conversion item, press the Add button on the toolbar to add the task to the ‘Conversion Task List’. Repeat Steps 1-4 as needed to add additional conversion tasks to the conversion job.
Press Convert when ready to begin the conversion job.
Repeat steps 1-4 as many times as necessary to create a sophisticated ‘Conversion Job’. Conversion jobs can be saved, restored, and edited; they may also be specified and run from the command line. See the File menu to save or restore a conversion job.
NOTE: In the picture above it shows the settings to convert every PDF found to a TIFF file. Notice the proper way to specify all files in a folder by specifying the wildcard *.PDF and *.TIF. The next topic discusses converting whole folders of files in more detail.
NOTE: You can build 'Conversion Jobs', consisting of one or more Conversion Tasks, which may be saved, restored, and edited. Once a ‘Conversion Job’ is saved, it then may also be specified and run from the command line or batch file, making automating complex tasks a snap.
More:
Converting Whole Folders of Files