From the start kill the two enemies in the room and then use the box to get out of bounds on top of the door. Then turn around and ride the out of bounds wall around to where you can jump over the fence. The wall will try to shoot you forward and into the void so watch out for that. This strat saves 45 seconds over the current world record of 29:07.

Here's a video of the out of bounds movement I found the day before finding the above variation. This route doesn't really save time as it's presented here but there could be some things in there worth investigating further.