Yes, you can change the upload maximum limit from beyond 100MB. This requires you to do a few things. First, you need to increase the upload max limit within PHP (the most that you can set this to is 1.95GB). Once you have changed that, simply modify your template file so that it matches what you have set in PHP. The "100MB maximum" text that you see is just that, text. It is meaningless (it is just used to tell people what the limit is). The real limit is set in PHP.