Here is xtgem Forum Twig tutorial:ADVANCED USERS ONLY
Xtgem uses twig templates to create the markup of forum blog and guestbook
Twig is a php template engine the documentation for the template development tools is available at
http://twig.sensiolabs.org/doc/templates.html
You do not need a php upgrade to use these twig files
First create a folder named_xtgem_templatesin the main file browser (root)
this folder is where xtgem expects to find the main twig files
Note: to allow the use of "upload by remote server" most of the files have a .js extension this should be removed after upload
Do not edit twig files with the building tool you must use the code editor
FORUM
There are two twig files for the forum the main file

http://syntax.xtgem.com/_templates /xtforum.twig.js

And the blocks file

http://syntax.xtgem.com/_templates /my_blocks.twig.js

both are required