Hi Purwedi, another fine plugin you have produced, thankyou.
Works fine for ads to appear after the first paragraph- options 1,2…
I wanted to place an ad to appear before first paragraph, by selecting Option – Place ad after paragraph no: 0
Nothing appeared.
Is it easy to change code in really-simple-ad-injection.php somewhere after line 169, an easy code mod so 0 (zero) option works too?

https://www.ads-software.com/extend/plugins/really-simple-ad-injection/