Using web3 version 0.1.0 and ethabi verion 4.0.0/4.2.0.

Traced back error message form rust-web3 to ethabi (received the same result from ethabi-cli):

Message("Error(InvalidName(\"DLL.Data storage\"), State { next_error: None, backtrace: None })")

DLL.abi throws InvalidName due to the following snippet from the JSON file:

{
		"constant": true,
		"inputs": [
			{
				"name": "self",
				"type": "DLL.Data storage"
			},
			{
				"name": "_curr",
				"type": "uint256"
			}
		],
		"name": "getNext",
		"outputs": [
			{
				"name": "",
				"type": "uint256"
			}
		],
		"payable": false,
		"stateMutability": "view",
		"type": "function"
	}

It seems like it cannot handle "type" being DLL.Data storage. Once changed to a different type such as uint256, error subsides.

DLL.abi.txt
DLL.bin.txt
DLL.sol.txt