Unable to install theme

Hi, I´m not a member from Kutethemes support... but I think I can help you.
This error is not in theme but in your hosting default configuration.

If you have access to "php.ini" in your host, modify or add following code below:
max_execution_time 60
memory_limit 128M
post_max_size 48M
upload_max_filesize 48M

If you can´t do it, ask your hosting about it.

Or you can unzip the folder name "kute-boutique" inside of "wp-content/themes/" if you prefer to do it manually.