Quote: "For the quicksand you could have an invisible lift that moves down at a very slow speed."
You mean something like this? This is just a design concept from our Ancient Tombs 1 game development, but was rather simple to do. One just needs to do some retexturing of segments/entities needed.
First, we used the lift and textured with the sand texture from Rosstradamus' Dark Egypt pack. We then made the room and left one floor square bland where the player would "sink". Next we used a wall entity with the sand texture rotated in place to cover the hole in the floor, but collision is off so the player passes through. Next we used Dark Egypt's Room Basic 01 Wall 01 and textured it with the sand texture to form a "sand pit". Next we place the lift just slightly above the entity wall that is rotated to cover the floor hole, and adjusted the lift speed to "15". A trigger sits in the pit and as the player sinks down, that's where Rolfy's sandstorm script comes into effect. After that, player dies.

There's no problem that can't be solved without applying a little scripting.