Okay, though I am new to irrlicht I am not new to programming or open source developments and I have an interesting story to tell:
Before MMORPH's were a dime-a-dozen I wanted to look into making one, so I went around and scouted out the various graphic's engines. I eventually found Crystal Space and a project people were working on....so, wanting to try the project I downloaded it.
The MMORPH had potential (*sigh*) and I found a few bugs that needed fixing in the networking protocols they used. I got hired on as their 'Network programmer' until I decided to leave the project from differing opinions.
The point? If you give your source out you may end up getting a surprise like the owner in regards to me. I downloaded it just to try and winded up adding options, code and bug-fixes.
This project (the engine and games made via the engine) need people to be able to look at the source to gain a hint on the direction they need to go, and possibly to give back some input regarding the project.
Now, after saying that, I will agree that there are people who would rather cut-and-paste a project together, or at least parts of a program. Let them, they will (A) become frustrated and quit the project altogether; (B) ask so many questions that their code will change from the origional/hybred to something new and useable or (c) scrap the copy-paste code and restart.
Anyone who went to school for programming knows that copy-paste code really, really, REALLY sucks.
My first 2 cents

Umm, don't look at me that way. I'M not the dead one here.
--The One True Marshmellow