Adblock Issue and option to check

I have issue on installing adblock on my router. Everything works well. as of now in past many years, I dont find any issue. I recently doubted my router on download. It reported in GB's when only adblock is installed on router and nothing else.

I also noticed, its status is always "Busy" as shown in below image. is there any way for disabling download forever once its download for first time ?

or is it possible to create our own list instead of downloading from sources ?