The Image Prepare competition site makes running camera club competitions a breeze.
Club membership can be uploaded from a spreadsheet and members can then be invited to set up their password. Once that is done submissions to competitions can be made. Once the entry deadline has passed the competition secretary downloads a zip file containing a randomised set of images and a spreadsheet listing those entries. The download can either be in a format suitable for FFPx or DiCentra. Load the images into your projection software, run the competition, export the results and upload the file to that the results are published to the website.
It is impossible to enter an image which doesn't comply with the requirements. If a member's upload doesn't comply then he or she can click the 'Fix It' button to sort out the problems.