Why did you choose for a Fluid Boxes responsive project if you want to see it only on a Surface Pro? First thing to know is that the screen resolution is not the same as the browser resolution. It is the Browser resolution that should be taken into account when creating an eLearning course. At this moment I do type on a Surface Pro, which has indeed a retina screen 2736x1824, with a display percentage of 200% as default setting. However when checking the browser resolution of my system (viewportsizes.com) it is 1368x821. You have to decrement those numbers with the pixels taken by the browser or the LMS, and eventually the playbar. Your start resolution is not correct. I has not much sense to develop with a resolution that has to be downscaled on all devices.
Secondly: if the goal is to watch on a Surface Pro, using a non-responsive project with rescalable HTML output would have been a better choice. I publish most of the tutorials for which I offer links in my blog to that output. Maybe this post can clarify the differences between Rescalable, responsive with Fluid Boxes and responsive with Breakpoint Views:
https://elearning.adobe.com/2017/11/tough-choice-breakpoints-or-fluid-boxes/
Here is a link to one of my published Rescalable tutorials:
http://www.lilybiri.com/published/TimelineBlog/index.html