If you want to continue rendering from frame 788 onwards, you can edit the script file in Notepad or some other text editor. You need to do two things: 1) delete all the lines that correspond to the frames you don't want to render, and 2) change the number next to the InitAnim command (change it from 1 to 788). You need to do both these things to make the script correctly render from 788 onwards.
Matt