plugin doenst work - js file(s) is(are) missing in head

i've just installed your plugin, but i'm not able to make it work. js files just dont load. i have no js error on the page, i've tried desactive all plugins, nothing helped. so i really hope you will.
I can see html elements but no js event is fired.
thanks for any advice

wp v3.8.1, appointment+ plugin v1.4