I'm trying to fork a X13 coin I like but i'm missing something important.

I've made all the code changes I want, then I use GenesisH0 to get merkle root, genesis hash, pszTimestamp and nTime, add those to the code and compile.

But when I launch the windows-qt i get an Assertion failed ! error.
Expression: block.hashMerkleRoot == uint256("0xb8a521c89f62af3b80565dec94e5a08eafe4e15b372550f77409832a20cf4398")

Please someone help me out. What am i doing wrong ? Why is it not accepting my merkle root?