How do I get into the altar?

Hint 1 of 10:

You will need to force down the door.

Hint 2 of 10:

Or at least find someone who can force it down for you.

Hint 3 of 10:

Or something.

Hint 4 of 10:

The triceratops will do the job for you if it has the right motivation.

Hint 5 of 10:

Doesn't it look a lot like a bull?

Hint 6 of 10:

Bulls are attracted by red.

Hint 7 of 10:

And part of your red dress got caught on the way into this area of the game.

Hint 8 of 10:

It's hidden back on the entrance screen -- if you could only get there.

Hint 9 of 10:

The tyrannosaurus will take you there if you ride it.  See the previous
question for help in getting the red cloth.

Hint 10 of 10:

But you also need to make sure the triceratops is facing in the right
direction when you use the cloth on him.