This made it in to the next update for the version 6 beta 3, which should be out in the next few days.
We do have the Percent Change Bar Type. You would select it from the Bar Type dropdown menu on the top toolbar.
I would like to set a stop/limit order to a specific time because i want to avoid the market open. For example the stop/limit order should be relevant only after 10:30 am.
If you're looking at creating an automated strategy that enters at a specific time, like 10:30am, we don't currently have a time of day option built-in. But, you can create a custom strategy using our Java SDK, which would allow you to do that. I can put your name down for this feature request, as I believe it has been requested before.