AC3D is used for flightsims, such as Openplane and Targetware.
You will find that it's very easy to create and texture 3D models in AC3D. The texture coordinate editor is as good as other standalone tools costing the same or more than AC3D itself - especially as it is integrated within AC3D.
The trial is designed so that you can evaluate the product. We recommend to look at the manual and try the software to see if it suits your needs. There are also tutorials and a personal learning guide to get you started.
AC3D's simple and powerful interactive interface is what sells AC3D. The ability to finely position single vertices and perform individual operations on a single surface is what attracts many people. for a comprehensive feature list see
www.ac3d.org/pages/features
If you have any specifc questions, post them here and we'll do our best to help.
Andy