Just a minor suggestion here, but it would be great if there was the 'Search Scirra.com' box on every page of the website as it seems to only be on the 'Forums' and 'Tutorial' pages.
Also, when you do a search from the 'Search Scirra.com' box on the pages where it is available it just displays 'www.scirra.com' at the end of each post and you have to put your cursor on the topic name to see the link on where the topic was posted.
Again it would be great if there was the same 'Search Scirra.com' box on all the pages so when you did a search everything would come up in the search results.
Google Custom Search would be a great way to go and it seems the site is using Google since the search results page say powered by Google, but again it would be great if the search box was available on every page of the site as well as displaying the link addresses like they are displayed in a search from Google.com in order to get the most relevant results quickly since in many cases now I have to go to Google to search the scirra.com site.
For example, I was interested in adding levels to the 'How to make a Platform game' tutorial and the best way was just to do a Google search with the parameters 'Construct 2 add levels', 'scirra.com add levels', etc.
For instance compare the search 'scirra.com add levels' using the 'Search Scirra.com' box and Google.com to see that the results and their format using Google.com are more helpful.