It could either be a model error, map hammer lighting error, OR a scene error. Have you tried exporting an image of the sequence, poster or movie clip?
If not, try it. If everything is fine, it's a map or scene error and not a big deal. Sometimes maps aren't built with good internal lighting if they're user made. Adding a scene light can fix that sometimes as well.
Good luck.

If it's not a conflict of assets, large scenes, files or lengthy shots can be horrible to ram buffering. As a 32-bit program the sfm is limited to 2gigs of ram(even if you have more), but simply expanding it can allow the file to properly load.
This was the case with a 360 degree video I made for the sfm, downloaded a simple "Large Address Aware" 32 bit expander, selected the sfm application and patched it. Sorry I don't have a straight link, but it is verbatum called "Large Address Aware"

It could be your computer isn't good enough, you're using an sfm_resolution -1080 launch option viewport for working(you shouldn't), or you're camera settings are set to max sample overrides(not a great idea before rendering either).
Another fix if nothing else rings true, disable scene lighting. Right click, and uncheck enable lighting. It's best(and fastest) to work in an unlit enviroment(i do a lot) and even if you haven't placed any lights in the scene, the map comes with a bunch of pre-built lighting created in the hammer editor.

Hope that helps!
-b

Originally posted by Thrawn:

So, I'm having yet ANOTHER problem in SFM! This is OVERKILL.
So, I've been working on this Science Fiction Space Adventure project for a while now, it's under the name GalactiQuest. It's a long SFM film that has taken me a while to make. Well, I'm having a problem I've never had before.

See, I am using the Sci-Fi assets models, they're great for a Science Fiction adventure. Welp, I'm having a problem with the humans. (Models are here: https://sfmlab.com/item/862/)
The humans' eye controls don't work at all.
For example, watch my video about it:
https://www.youtube.com/watch?v=a2mOa9NL0xU

Is there something I'm doing wrong here? Please tell me, because I really like these models and I want to use them.

Well, that is all for today. Any help, as always, is appreciated.

Just from a brief look at your video it appears as though you rely too heavily on those sliders. Every model in the SFM uses a viewTarget null object in the head group. You'll want to control the eyes that way a majority of the time by placing it near or in the direction of the object you want a character to be looking at and then use the sliders as supplements. If you leave the local viewTarget alone completely, chances are head movement and rotation will make the eyes look as if they move drastically in one direction because the viewTarget's natural position is very close to the head.

Hope that made enough sense for you to figure out.

-b