There must be something wrong with the deployment location of your.
Now the solution if the theme is your problem. There have been some changes in the index.html files.
Compare the files index.html and index3.html from your theme with the files deployed by the modeler.
The index files deployed by the modeler contain some additional lines like this:
<script type="text/javascript" src="ui/js/en.js"></script>
<script type="text/javascript" src="ui/js/login.js"></script>
Copy all the missing lines from the deployed file to own index file from the theme and try if your startpage still looks the same and if you can login.