I'm not so much concerned about latency but about getting the stop triggered at all.
Had this happen last autumn during one of the volatile days: was in a short with a stop that should be triggered to move to break- even after the trade was in the green for 15 ticks. I saw the market move down to this threshold (IQFeed) but IB's snapshot feed missed this threshold by several ticks.
While I (stupidly) tried to understand "what had happened" market turned around and went up through my original stop loss in the blink of an eye.
Usually I don't use trailing stops and such stuff but the volatility then made me use them.
This is fixed in the latest revision of 915. If you have not already updated please update with Help >> Download Prerelease or download the non-CLR version.
If you have any difficulty with data sharing between instances of Sierra Chart when using a Trade DOM, then reopen a Trade DOM through File >> Find Symbol. This is now supported to open a Trade DOM from a remote instance this way. It is important to reopen it because some internal variables will be properly set in that case.
In regards to the question about trailing stops and using data from remote instances, trailing stops will always be driven by the connected to data feed in the copy of Sierra Chart where the trailing stop has been submitted from and is being managed from. This may change in the future.