UT 99 (v436) - Intro is very slow (< 5 fps)

[r-a-sattarov]

After commit https://github.com/dpjudas/SurrealEngine/commit/3fb13da729a07604d17d532baaaf5d223ee30abe intro started playing at the beginning of the game, but it is very slow (even the Game menu is lagging). But after I start playing on the map with bots, performance returns to normal.