Rookie in Airgun PCP World -SOS Kalibrgun Cricket 2 Tactical 45 cal .22

Hello Airgun Nation, greetings from Peru.
I am a rookie in the Airgun World, around ten years ago I had to gave away my shotguns and shells. Since then, I always was thinking to shooting again. I found in PCPs a great opportunity to get back.
After waiting for more than two years, recently I bought a Kalibrgun Cricket 2 Tactical 45 cal .22. Really, what I wanted to buy was a FX Wildcat III, but it never arrived to my country. In Peru, the market is small and it is not easy to get a good PCP Rifle. There are many Chinese, Indian, Turkish guns but I didn't want any of those. Fortunately a Dealer import some Kalibrgun, Air Technology and othe Chez guns . I chose the KC2T 45 cal .22 to start in the Airgun World.
Given the above, after I bought the KC2T 45 cal .22, I got an Element Optics Helix Scope 6.24x40 FFP mounted on Vortex Optics Pro (extra high) weavers. Also, I bought two DonnyFl moderators Tanto and Tatsu. I'm already bought many cans of JSB Exact Jumbo Heavy 18.13 and Jumbo Monster 25.39 pellets... given all this, I will ask for your help guys.
You all have a wide experience with PCPs and maybe some of you know well the KC2T 45 cal .22 too. I have some questions that maybe some of you can answer and help me:
1) What FPS do you recommend me to get the best performance using each of the above pellets type?
2) For this airgun what Far Zero do you think is the best to set?.
3) I watched a video in Youtube, where there was used Loctite 243 to tight the spring regulator. How can I remove the Spring regulator screw to apply some Loctite correctly?.
4) Someone can tell me what was the longest and accurate shot made with this Rifle? therefore, thinking on his/her experience, to reach the longest accurate and possible shot distance , what tips would you give me to consider?
5) When you are not using the Rifle, what pressure do you recommend to leave in the air tank?
6) When you fill the air for first time, What do I have to consider? I heard that I have to keep the cocking side lever open, is it true? what else?
7) Do I have to reach the 300bar indicated in the manometer, or is better to load up to 250bar to protect the O-rings?
8) Please give me any other tip that you would consider useful and valuable ...
Below a picture of my gun in its case .... Thank you in advance for all tips and time...
KC2T 45 cal 22.jpg