Suggested:
// change the hash of BIPs to your genesis hash (see the genesis section) is your genesis hash
// do it for main, testnet and regnet.
consensus.BIP16Exception = uint256S("0x???");
consensus.BIP34Hash = uint256S("0x???");

=>  you are doing an altcoin so all the BIP should start at Genesis. So, take the hash from your blockchain and yes it should be the same as the assert.

// fix the checkpoint data with your genesis hash, do it for main,testnet and regnet
checkpointData = {{{0, uint256S("0x???")},}};

=> go in your blockchain and add blocknumber, hash as checkpoint so that if someone change the the blockchain on purpose, the wallets will reject the change. Do it periodically so that you solidify your blockchain against attackers.

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Suggested: IsNullDummyEnabled has the same problem, do the same to that function.
Question: Cant find it?!! Is it in validation.cpp on the latest bitcoin version?

=> this I do not understand.

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Suggested:  Find this “return state.DoS(100, false, REJECT_INVALID, "bad-cb-height", false, "block height mismatch in coinbase");” and comment it.
Question: Cant find it?!! Is it in validation.cpp on the latest bitcoin version?

What I do find is this...

            return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-height", "block height mismatch in coinbase");

=> the genesis block will shoot this error, so you need to comment it in order to have your wallet to mine, or you will not mine.
Also all similar errors du to SEGWITH needs to be commented, at least for the first blocks.
then you can reinstall all the BIP tests that were blocking the mining, let say at block 1000 for example and change chainparams.cpp accordinally.


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