Hi @tyty24, Thanks for leaving me a comment; i was wanting to hear from someone at the CRS event; Looked like a great conference!

Apologies for the delay; If you have BTC in an outside wallet you would need to deposit it with Bitshares first (you can use the Deposit/Withdraw tab in the wallet) and use the OpenLedger Gateway and select Deposit.

Once you have your BTC in Bitshares you can buy BTS of the Decentralized Exchange (Exchange tab).
Once you have Bitshares (BTS) you could borrow/short BitUSD into existence using your BTS as collateral. Then once you have BitUSD you could buy what ever you like (BitBTC, more Bitshares, the latest ICO or convert it back to fiat if you really want to). Either way the Bitshares you used as collateral are still your but they are 'locked' as collateral until you pay back your bitUSD debit and if the CRS event is anything to go by you would just hold that collateral on the network until you can buy back your borrowed BitUSD for cheap.

Then you have had your cake and eaten it too :)