Could you try to make a new blank project and add the mobile advert plugins, using the same way you add mobile advert plugins in your origin project..
Is it show the same black screen ?
or could you provide a lil bit more information ? maybe screenshot piece of your event/code which related to mobile advert ?
If there is nothing in your event sheet, could you screen shot your Mobile Advert's Properties panel after add it in the blank project ?
What version of Construct 3 that you use to create that mobile advert ?
what is your browser ?
Maybe.. try clear all your browser cookies, and reload a fresh Construct 3 editor ?
I just use mobile advert in my project, and it look normal.