Not really.

Free to enter the courtyard and gardens. A fee to enter the castle (2 different tours), a second fee to enter the tower/museum and a third fee is you want to tour the horse stable museum.

Not sure but i think closed on Chritmas and new year days

I only did the free walk; not a guided tour. as far as I know it’s still Open for free walks but you have to pay to use the toilets

There is a ticket office right inside the courtyard.

Yo lo visité por fuera, que es gratuito, puedes entrar gratis también en los jardines que están arriba y ves el teatro giratorio. Pero sé el precio para entrar por dentro. Te va a encantar la ciudad. Y las vistas desde el castillo son preciosas. Con un poco de suerte verás los osos pardos que están en el foso.

Hope is not too late. It is more economical for us to buy some local currency, as the Euro calculations are to our disadvantage in tickets boxes and entrances.

You can. There's a small bus service. It is about 20 minutes to walk if you prefer: it's downhill on mostly quiet roads and on some pedestrian-only paths. Coming back is a bit more challenging.

The best "view points" are freely accessible (the viaduct to the garden etc.) If you want to climb the castle tower, you will have to pay. For opening time check the working hours of the whole castle complex. There are also some marvellous views available from the churches downtown, but have no clue how they open and what to pay.

You do not have to pay to take pics through those arched -"windows/holes". You are free to walk around unless you want to get inside the castle for a tour. Enjoy..!