This template is very light weight and has fast load speeds. You can see from our demo that it loads in 3.7 seconds:https://gtmetrix.com/reports/www.shape5.com/VhBQvBir
If you are having latency issues that would be because of content issues on your page (eg: large images), or because of performance issues on your server.
The php file you mentioned is just a flat file that calls all the files in a single location for less http requests. You can turn off compression if you would like and it would not really effect performance, the main point of the compression is less server requests. However, that will most likely not solve your problem as that file isn't making any calculations, it's just a cache file that is called and only refreshed periodically.