I'm having the same problem, running a quite a share of mods also. Would really lke some help :) Random ctd in exterior, near markarth, near whiterun plateau, you name it. No error message also.
This is somewhat of a news how I got ANYWHERE out of solstheim: What I did was typed "coc qasmoke" in raven rock - there I waited for 3 days. Next Exit the game, turn your distant object detail to "Low" in the skyrim launcher settings - Now run the game, load the autosave in the qasmoke place and type "coc riverwood" I successfully teleported to riverwood - was the only way I got somewhere - the stuck screen issue kept going worse until it persisted. Hope it helps and I will let you know if i'm ok now.
Is there such a mod, if not, is it possible to create one. The current system is so awkward...run - instantly walk. absolutely non-immersive. Thanks for any feedback.