I completed the online application about one month ago, and here is what I can tell you: The paper application that I printed to help me prep for the online application does not have a word count restriction, but the online application does. In fact, for each project you can only type up to 550 characters, and that includes spaces. Up to this last sentence I just wrote, there are 534 characters. As you can see, that is not a lot!
If you have already written the details for each Process Group like I did, you will need to sum up each project. I just hit on what’s most important: the deliverables and how I managed the project. The good news is, PMI has done a great job structuring the online application. It’s extremely easy to enter all of your project info and double-check that you did not miss anything.