Please don't lubricate a new engine with WD40. The two oils are not even in the same zip code of similarity. making the starter spin the engine over to prime the oil pump lines is only going to destroy your starter & wear down your battery. No need to do that IMO. Running a ski across a like with no injection oil will destroy it. Letting it idle on the trailer to prime a well pre oiled engine is just fine.
I understand the fear, but think about how small amount of oil is added at idle & how much is already in the case halves.
Back to the smoke thing. I just rebuilt a 951 DI, & used a lot of injection oil during the rebuild. a couple ounces in the case bottoms, crank & pin bearings, rings, etc. My pump is primed & injecting. It really doesn't smoke all that much as compared to my carb'd skis. Could be something with the DI design? Not sure. I can smell the oil in the exhaust, but not much smoke in the shop.