Cornerstone Off-line Player and Articulate Courses

We are in testing some existing courses in Cornerstone LMS.  In addition to the browsers, we want our users to be able to take these courses in the Cornerstone Off-line Player.

The courses were developed in Storyline 2.  They seemed to behave as expected in the Off-line Player.  We decided to upgrade/save them in Articulate 360 with the setting of HTML5 first with a Flash backup.  This resulted in some corrupted fonts when played.  We then changed the settings to Flash first, HTML5 2nd.  This seems to resolve the issue.  However, I've been advised that we should be running away from Flash, and that we may have issues with the courses within a couple of years if we use the Flash first setting.

Does anyone have any experience specifically with the Cornerstone Offline Player and are there any known capability issues with storyline courses? Are there technical requirements to ensure courses developed in Articulate 360 work with Cornerstone and the Offlline Player.  Should I be concerned about the setting of Flash First, HTML5 second?  Since we need these to also play in I.E., Chrome and the Cornerstone Mobile Application, will the setting limit the shelf life of the courses?  Thanks.