By paying for your subscription I can continue to work on the development on our extensions (so your feature request & suggestions are welcome!) and provide you great support.
Sure! The extension will remain fully functional. After expiration of your subscription you will no longer be able to download new releases and request support.
YES. The extensions are fully open source and the code is NOT encrypted in any way.
You are free to change the code to your likings.
However: If you alter the extensions files, We can no longer provide support on any problems you encounter.
Also if you update or reinstall the extension, all changes you made will be lost.
So it is better to overrule functionality via template overrides or custom plugins.
For changes in styling it is best to overrule style classes through the css stylesheet of your template or add a custom stylesheet.