There is an issue with the staking-mechanism that needs to be addressed.
I have a working copy of the blockchain from 2 May 2017.
A few days after the above date, I did a large transaction to another wallet.
The client went off-line for a while.

When I started it again, it went into staking the entire sum and got stuck.
I also tried to mine again, but the peer on the other side didn't accept my blocks.

Recently I experimented with a truncated version of the chain.
I used one client for mining. Another one was staking for hours.
I made a transaction that included a large amount of newly-mined blocks to a third wallet.
The first time, it worked.

Then I tried this again. The second client suddenly ceased producing POS blocks.
A huge amount of coins disappeared.
checkwallet didn't report any errors.

I then copied a backup of the blockchain as well as the wallet into the StarCoin folder.
The client loaded the blocks, and all the coins were retrieved.
However, there was no staking going on.

The old chain from 2017 now has been mining for two days.
So far, no POS blocks since I do not dare put any old wallets on-line again - just in case.
I believe it once was planned to get rid of staking altogether.

Sorry if I sound negative, but I only try to help.