@ron_dev thanks for your hard work. It really shows it in the plugin. It's a great plugin to build custom/advanced search filters.
The checkboxes idea is a must, especially when you've got conditions like "and" where all of the selected needs to match. This condition is useless at this point in time since users can't pick more than one option.
If there is a custom way to do this, i'd love to know.
Anyway, take your time and thanks for a great plugin.