Ajaxplorer Meta plugin creation

Hi, I'm using the latest version of Ajaxplorer (4.3.4 RC4) for a project. The software has most of the functionality I need, but it is lacking in some meta data functionality. On top of the current meta data (text, stars and css), I want the option to add date and number meta data. This data should also be searchable using the standard "greater than", "less than", "equal to" and "between" functions for numbers and dates. I want this delivered as a plugin that is similar to [login to view URL], preferably under the AGPL license, so that it can be freely distributed to other users. Please only respond if you have experience with Ajaxplorer ([login to view URL]). Thanks!