I've recentelly had to build a mobile app that could download games build with Construct 2 and run locally, the solution I've got is handle the game data and sounds in a different way. And here is my solution:
1- Export your game with the minify option unchecked
2- Change the way Construct handle sounds, to do that we need to open the index.html and add right after the code:
<div style="display:none;">
<script>
window.playAudioAux = function(url){
var output = url.substr(0, url.lastIndexOf('.')) || url;
var url1 = output+'.ogg';
var url2 = output+'.mp3';
var url3 = output+'.m4a';
document.getElementById('myAudioogg').src = url1;
document.getElementById('myAudiompeg').src = url2;
document.getElementById('myAudiomp4').src = url3;
document.getElementById('myAudio').src = url3;
document.getElementById('myAudio').load();
document.getElementById('myAudio').play();
}
</script>
<audio id="myAudio" controls>
<source id="myAudioogg" src="" type="audio/ogg">
<source id="myAudiompeg" src="" type="audio/mpeg">
<source id="myAudiomp4" src="" type="audio/mp4">
Your browser does not support the audio element.
</audio>
</div>
This will create a new way to run audio. And now we have to change the c2runtime.js where it calls the sounds, so find:
function C2AudioInstance(buffer_, tag_)
{
And add right after that
playAudioAux(buffer_.src); return;
This will stop the normal call of Construct and call the function that we just added on the index.html
3- Most(maybe all) browsers see requests from local as a security problem so we have to load that game data.js in a different way, open it so you can copy its content. Also inside c2runtime.js find the following code inside requestProjectData function:
xhr.open("GET", datajs_filename, true);
var supportsJsonResponse = false;
And then add after that this code:
self.loadProject(FULL_CONTENT_INSIDE_YOUR_DATA.JS); return;
This will load your game content and cancel the request to load data.js.
4- Inside index.html comment the alert about running the game locally like this:
//alert("Exported games won't work until you upload them. (When running on the file:/// protocol, browsers block many features from working for security reasons.)");
That is it! :D, It runs fine inside firefox, android webview etc. The only one that still doest run it is Chrome for security reasons...
Hope it helps anyone with this kind of problem.