OK, I can see how the yard connects to the main but it's completely backwards from what would normally be done. As your train pulls into the yard, you only have the two short tail tracks for the motive power, the rest of the train will be fouling the yard lead. There's no runaround and it would seem to be impossible to be able to put cars in the middle of the train inot any of the yard tracks. It looks like you are still early in construction. If there's any way to make the yard connect to the main from the bottom left of that picture, I would do it now. As it sets, that yard is going to be a source of unending headaches.
There's a good article about Insulfrog turnouts at
http://www.loystoys.com/peco/about-insulfrog.html. Assuming you are using DCC, all you need to do is wire the frog so it's live all the time. If you are using DC and power routing, you need to wire the diverging and straight routes so the frog remains dead until the points are thrown for the direction of travel.