diff --git a/chain/tests/data_file_integrity.rs b/chain/tests/data_file_integrity.rs
index db95dbe8e..786c3bbd7 100644
--- a/chain/tests/data_file_integrity.rs
+++ b/chain/tests/data_file_integrity.rs
@@ -81,7 +81,7 @@ fn data_files() {
 			let mut b = core::core::Block::new(&prev, vec![], difficulty.clone(), reward).unwrap();
 			b.header.timestamp = prev.timestamp + time::Duration::seconds(60);
 
-			chain.set_block_roots(&mut b, false).unwrap();
+			chain.set_txhashset_roots(&mut b, false).unwrap();
 
 			pow::pow_size(
 				&mut b.header,
@@ -117,7 +117,7 @@ fn data_files() {
 
 fn _prepare_block(kc: &ExtKeychain, prev: &BlockHeader, chain: &Chain, diff: u64) -> Block {
 	let mut b = _prepare_block_nosum(kc, prev, diff, vec![]);
-	chain.set_block_roots(&mut b, false).unwrap();
+	chain.set_txhashset_roots(&mut b, false).unwrap();
 	b
 }
 
@@ -129,13 +129,13 @@ fn _prepare_block_tx(
 	txs: Vec<&Transaction>,
 ) -> Block {
 	let mut b = _prepare_block_nosum(kc, prev, diff, txs);
-	chain.set_block_roots(&mut b, false).unwrap();
+	chain.set_txhashset_roots(&mut b, false).unwrap();
 	b
 }
 
 fn _prepare_fork_block(kc: &ExtKeychain, prev: &BlockHeader, chain: &Chain, diff: u64) -> Block {
 	let mut b = _prepare_block_nosum(kc, prev, diff, vec![]);
-	chain.set_block_roots(&mut b, true).unwrap();
+	chain.set_txhashset_roots(&mut b, true).unwrap();
 	b
 }
 
@@ -147,7 +147,7 @@ fn _prepare_fork_block_tx(
 	txs: Vec<&Transaction>,
 ) -> Block {
 	let mut b = _prepare_block_nosum(kc, prev, diff, txs);
-	chain.set_block_roots(&mut b, true).unwrap();
+	chain.set_txhashset_roots(&mut b, true).unwrap();
 	b
 }
 
diff --git a/chain/tests/mine_simple_chain.rs b/chain/tests/mine_simple_chain.rs
index 95140b988..092facd62 100644
--- a/chain/tests/mine_simple_chain.rs
+++ b/chain/tests/mine_simple_chain.rs
@@ -65,7 +65,7 @@ fn mine_empty_chain() {
 		let mut b = core::core::Block::new(&prev, vec![], difficulty.clone(), reward).unwrap();
 		b.header.timestamp = prev.timestamp + time::Duration::seconds(60);
 
-		chain.set_block_roots(&mut b, false).unwrap();
+		chain.set_txhashset_roots(&mut b, false).unwrap();
 
 		pow::pow_size(
 			&mut b.header,
@@ -365,7 +365,7 @@ where
 	K: Keychain,
 {
 	let mut b = prepare_block_nosum(kc, prev, diff, vec![]);
-	chain.set_block_roots(&mut b, false).unwrap();
+	chain.set_txhashset_roots(&mut b, false).unwrap();
 	b
 }
 
@@ -380,7 +380,7 @@ where
 	K: Keychain,
 {
 	let mut b = prepare_block_nosum(kc, prev, diff, txs);
-	chain.set_block_roots(&mut b, false).unwrap();
+	chain.set_txhashset_roots(&mut b, false).unwrap();
 	b
 }
 
@@ -389,7 +389,7 @@ where
 	K: Keychain,
 {
 	let mut b = prepare_block_nosum(kc, prev, diff, vec![]);
-	chain.set_block_roots(&mut b, true).unwrap();
+	chain.set_txhashset_roots(&mut b, true).unwrap();
 	b
 }
 
@@ -404,7 +404,7 @@ where
 	K: Keychain,
 {
 	let mut b = prepare_block_nosum(kc, prev, diff, txs);
-	chain.set_block_roots(&mut b, true).unwrap();
+	chain.set_txhashset_roots(&mut b, true).unwrap();
 	b
 }
 
diff --git a/chain/tests/test_coinbase_maturity.rs b/chain/tests/test_coinbase_maturity.rs
index 30d7ab670..162b8eef4 100644
--- a/chain/tests/test_coinbase_maturity.rs
+++ b/chain/tests/test_coinbase_maturity.rs
@@ -67,7 +67,7 @@ fn test_coinbase_maturity() {
 
 	let difficulty = consensus::next_difficulty(chain.difficulty_iter()).unwrap();
 
-	chain.set_block_roots(&mut block, false).unwrap();
+	chain.set_txhashset_roots(&mut block, false).unwrap();
 
 	pow::pow_size(
 		&mut block.header,
@@ -121,7 +121,7 @@ fn test_coinbase_maturity() {
 
 	let difficulty = consensus::next_difficulty(chain.difficulty_iter()).unwrap();
 
-	chain.set_block_roots(&mut block, false).unwrap();
+	chain.set_txhashset_roots(&mut block, false).unwrap();
 
 	// Confirm the tx attempting to spend the coinbase output
 	// is not valid at the current block height given the current chain state.
@@ -151,7 +151,7 @@ fn test_coinbase_maturity() {
 
 		let difficulty = consensus::next_difficulty(chain.difficulty_iter()).unwrap();
 
-		chain.set_block_roots(&mut block, false).unwrap();
+		chain.set_txhashset_roots(&mut block, false).unwrap();
 
 		pow::pow_size(
 			&mut block.header,
@@ -178,7 +178,7 @@ fn test_coinbase_maturity() {
 
 	let difficulty = consensus::next_difficulty(chain.difficulty_iter()).unwrap();
 
-	chain.set_block_roots(&mut block, false).unwrap();
+	chain.set_txhashset_roots(&mut block, false).unwrap();
 
 	pow::pow_size(
 		&mut block.header,
diff --git a/chain/tests/test_txhashset_raw_txs.rs b/chain/tests/test_txhashset_raw_txs.rs
index 067200523..7dbd6caa6 100644
--- a/chain/tests/test_txhashset_raw_txs.rs
+++ b/chain/tests/test_txhashset_raw_txs.rs
@@ -22,7 +22,7 @@ use std::fs;
 use std::sync::Arc;
 
 use chain::store::ChainStore;
-use chain::txhashset::{self, TxHashSet};
+use chain::txhashset;
 use chain::types::Tip;
 use core::core::merkle_proof::MerkleProof;
 use core::core::target::Difficulty;
@@ -40,8 +40,11 @@ fn test_some_raw_txs() {
 	clean_output_dir(&db_root);
 
 	let db_env = Arc::new(store::new_env(db_root.clone()));
-	let store = Arc::new(ChainKVStore::new(db_root.clone()).unwrap());
-	let mut txhashset = TxHashSet::open(db_root.clone(), store.clone(), None).unwrap();
+
+	let chain_store = ChainStore::new(db_env).unwrap();
+	let store = Arc::new(chain_store);
+	// open the txhashset, creating a new one if necessary
+	let mut txhashset = txhashset::TxHashSet::open(db_root.clone(), store.clone(), None).unwrap();
 
 	let keychain = ExtKeychain::from_random_seed().unwrap();
 	let key_id1 = keychain.derive_key_id(1).unwrap();
diff --git a/doc/transaction/grin-transaction.puml b/doc/transaction/grin-transaction.puml
index 771ec0e5d..80c12647f 100644
--- a/doc/transaction/grin-transaction.puml
+++ b/doc/transaction/grin-transaction.puml
@@ -13,7 +13,7 @@ entity "Grin Node" as grin_node
 
 note left of sender
 	1: Create Transaction **UUID** (for reference and maintaining correct state)
-	2: Set **lock_height** for output (current chain height)
+	2: Set **lock_height** for transaction kernel (current chain height)
 	3: Select **inputs** using desired selection strategy
 	4: Create **change_output** 
 	5: Select blinding factor for **change_output**
diff --git a/servers/src/mining/mine_block.rs b/servers/src/mining/mine_block.rs
index c2ff63b41..341fd8109 100644
--- a/servers/src/mining/mine_block.rs
+++ b/servers/src/mining/mine_block.rs
@@ -179,7 +179,7 @@ fn build_block(
 		b.header.clone().total_difficulty.to_num(),
 	);
 
-	let roots_result = chain.set_block_roots(&mut b, false);
+	let roots_result = chain.set_txhashset_roots(&mut b, false);
 
 	match roots_result {
 		Ok(_) => Ok((b, block_fees)),
diff --git a/src/bin/grin.rs b/src/bin/grin.rs
index 2a03e1bd5..e55ceca8c 100644
--- a/src/bin/grin.rs
+++ b/src/bin/grin.rs
@@ -51,7 +51,7 @@ use daemonize::Daemonize;
 use config::GlobalConfig;
 use core::core::amount_to_hr_string;
 use core::global;
-use keychain::{self, ExtKeychain};
+use keychain::ExtKeychain;
 use tui::ui;
 use util::{init_logger, LoggingConfig, LOGGER};
 use wallet::{libwallet, FileWallet};
diff --git a/wallet/tests/common/mod.rs b/wallet/tests/common/mod.rs
index a84da17f5..33671c9bc 100644
--- a/wallet/tests/common/mod.rs
+++ b/wallet/tests/common/mod.rs
@@ -145,7 +145,7 @@ pub fn add_block_with_reward(chain: &Chain, txs: Vec<&Transaction>, reward: (Out
 		reward,
 	).unwrap();
 	b.header.timestamp = prev.timestamp + time::Duration::seconds(60);
-	chain.set_block_roots(&mut b, false).unwrap();
+	chain.set_txhashset_roots(&mut b, false).unwrap();
 	pow::pow_size(
 		&mut b.header,
 		difficulty,