Seem to be unable to do this , from IB faqs it says : Attach a Trailing Stop to a Limit Order You can attach a trailing stop order to a limit order. The attached stop order is activated when the limit order is filled. You must route attached trailing stop orders through Smart order routing. To attach a trailing stop to a limit order Right-click on a market data line for a limit order. Select Attach Auto Trailing Stop. To modify the trailing amount, use the Aux. Price field. To modify the stop trigger method, right-click on the attached trailing stop order and select Trigger Method. To view/modify the stop election price, display the Stop Price column from the Order Row section of the Page layout When I click on the market data line there is no selection attach auto trailing stop . also I don't see smart order routing , there is a best routing
try this left click on current Bid price [assuming a sell] then left click on LMT you should see Trail at the bottom
Select "configure Hotkeys" click on action i.e. "buy", click on "create shortcut" Then click on the tab"customize". a screen appears where you can select attach a stoploss