The "FOV zoom" slider doesn't work at all -- does nothing.
When in external view mode, the bracket keys ([]) only move the camera distance forward and back even in zoom mode -- they don't move FOV zoom in and out when in zoom mode.
Clouds (ones that were loaded for the event with .sweath) at times disappear, especially in full-screen mode. You can get them back by being in external mode and using [] to move camera distance in and out. In internal mode, you need to jump to external in full screen, then back into internal mode to get the clouds to appear again.
If ships are maneuvering under someone's control, they don't appear in the film in the correct spot (compared to where they really were when you were flying).
"Gun cam" mode doesn't seem to work properly. Clicking on it sometimes just results in my bomber disappearing. If I do manage to get an actual view from a gunner position, then unclicking "gun cam" doesn't always get me back to normal internal view, and I'm stuck there. So, it is too buggy to use now.
"Bombsight" mode gives a bombsight, but not the one you see when flying. The crosshairs don't line up with your direction of travel and might not take into account calibration.
If the event had accelerated time (such as so that a day goes by in 3 hours), if you take a bunch of time in the viewer doing things, the sun can set earlier in your film than it did during the real event. But if you then stop the film and fast forward or slider travel to that same spot, the sun will be at the position it was during the running of the event. I.e., sun travel in film viewer can happen while your film is paused, it seems.
When you use the "Distance zoom" slider, it takes keyboard focus until you click on something else. Then, Page Up and Page Down keys, in addition to moving your camera position up and down, also move the slider back and forth. Incredibly annoying, as I often forget to click on slider, move it, then click off the slider before I'm pressing keys to move the camera position around. Then I have to go back and redo the zoom I want, click off it, then move head around again. This isn't technically a bug, but it would be *so* much better if nothing moved that slider other than [].