i have such message after adding radio buttons called lokalizacja with two options maybe because of polish letters in options:

Od:calendarerase
Do:calendarerase
Rodzaj gry
Rodzaj nawierzchni
Lokalizacja
Fatal error: Using $this when not in object context in /modules/mod_booking_search/tmpl/default.php on line 100

Hello,

Where did you add radio buttons?

I tried to add them as parameters as error showed up i changed it to select list

You mean properties?

Do you create new properties in template or object? I tried to simulate it, but it works for me in 1.5.9 version.
Maybe if you send us some printscreens here?

in template

i can send you access via email . I did it now check filtrerable searchable and error occurs on page