Jan Dembowski on "[Plugin: Ultimate Responsive Image Slider] Unable to save any settings in the free version."

Hi asabau,

The problem you are talking about is related to server configuration. There is limit of data posting on your server.

The variable post_max_size is responsible for this. You need to increase size of that variable using server php.ini file

Here the thread via you can increase the size of data posting variable - http://stackoverflow.com/questions/6135427/increasing-the-maximum-post-size

OR

You can contact to your hosting provider to update this for you.

Plugin has no bug regarding adding unlimited images, you can test plugin on local server where you found post_max_size is 20M.
So, you can add more than 250+ images easily in single gallery local server. If you increase size of post variable then adding images limit also increase.

We have created a "test" gallery on your site and its working fine, you can check.

Thanks