The plugin itself doesn't set any limits. You may be exceeding the time limit for a php script. If so, you can change the max_execution_time in php.ini to a higher value. The default is 30 (i.e. 30 seconds). If you don't have access to php.ini you can increase the time limit in epub/scripts/ebook.php. At line 118 insert: set_time_limit (0);
118: set_time_limit (0);
119: // $epub_ids = 'ditaa:win_filebrowser;;introduction;;v06;;features;;index:site_inx';
120: if(isset ($_POST['epub_ids'])) $epub_ids = rawurldecode($_POST['epub_ids']);
In theory set_time_limit (0) gives you unlimited time, but the execution time is limited by other factors as well. Probably better if you increase the time limit in stages until you get what you need. For instance set_time_limit (60), for 60 seconds, etc.