re: citadel xr2/xr2+?

I have the above alarm system stored in my property, about a couple of months ago we had thunder and lightning which normally triggers the alarm but on this occasion it did not. On lifting the cover to the remote keypad the tamper light was on, a steady light not flashing, the day light was also on steady together with the power light. The keypads were also lit but did not function. I looked up the issue on the internet and decided to replace the battery in the control panel along with the fuses. Again taking advice of the internet I checked the 4 PIR's all detected movement.
I seek your advice as to the next best move, I am aware that there are circuit boards in the system and could the thunder and lighting have caused damage.