But funny or not, my initial attempt has a White Bishop on d7 covering the b5-square. I rejected it 'cause it gives one more solution available to the puzzle, and I found it more esthetical without the Bishop. Thanks for spotting the flaw in the position. Just you wait, my next one will leave the entire site in awe! (Yeah, dream on:()

Speaking of engine, are there specific ones to verify is a chess puzzle can be flawless, or a normal one will do? And if there are, where can I procure it? Thanks.

I think a normal one would do the trick.

http://www.playwitharena.com/

+

http://www.stockfishchess.com/

or

http://www.cruxis.com/download/Houdini_15a.zip

Calculate the position some minutes. 

Thanks grasvater for the info! Will look at it

Alright! Here's my improvement from my first attempt.

White to move and mate in 8     (based on the toughest defense)

fingers crossed:)

It might have to be Nh1, not Nxh1, I'm not sure though.

Okay, I'll admit I kinda cheated.  I used Nalimov to help (it's mate in 3):

I dunno about Nxh1 but if that the case, I can do it a little less flashy:

White to move, mate in 7

Hello rooperi, I just sign in to check this contest...