owner can start the contract by calling start() function. Argument provided to the start() function is number of blocks. Average block time on main net is around 30 seconds as of this writing.

contributions are accepted by sending ether to contract address

when contract is deployed first, it is configured to act as a presale contract.

to switch contract to public ICO mode call advanceStep() function to set public ICO mode.
Be careful as there is no way to switch back to presale.

when the campaign is over, admin can run finilize() function to end the campaign and transfer unsold and dev tokens to individual wallet.
During finalize, token contract is unlocked and contributors can start trading tokens.

in case of emergency function emergencyStop() can be called to stop contribution and function release() to start campaign again.

option to withdraw contributions is provided in case ICO was not successful. Minimum cap hasn't been reached.

contributors can call function refund() to burn the tokens and receive back their contribution.

in order for contributors to be able to get refunds, following conditions have to be met.

1. Current block number has to be higher then endBlock.
2. Campaign did't reach minCap.
3. Step has to be set to Step.Refunding using prepareRefund() function. Function will expect exact amount of money which both presael and public ICO received during the campaign.

During ICO tokens are in the locked stage. In order to be able to transfer tokens, admin has to call function unlock() of token contract.