Hello guys and thank you for reading this!

My first problem with the Category Filter is with the Price. Every other field works, except the Price. I've tried to switch between slider and range but nothing. The link looks like: website/listings/category/price:0-88000.html and I get ERROR 404: Requested page not found!

On the other hand I use field-bound boxes and I've created one box with county (listings are in the same country) and thought to use filter on this.(because somehow I need to filter the result). As you can see in the next picture I get the infos from the showing listings...
Screen Shot 2015-03-27 at 4.48.09 PM.jpg
... except the category! (I understand the problem because is a category filter)

And, if I click on the filters I get a bad link like: website//price:1-100/ and 404. But if I type between slashes the link from the field-bound box everything works, even the PRICE! which is funny.
I also tried the refine search on the field-bound box but over there i got nothing:
Screen Shot 2015-03-27 at 4.59.51 PM.png

Did somebody else had one of this problems or could someone advise me with what to do?
Thank you!