I have an idea for fucntional water geysers, as seen in OoT, and MM, that doesn't use scripting. Just some elaborate screen warping and, four versions of the same screen. Admittedly, it's pretty limited in its usefulness, and I haven't fully tested it out yet, but it works on paper.
So lets assume our geyser uses an upside down waterfall graphic. Let's say it is three tiles high. The bottom most tile is a direct warp, not necessarily sensitive. The upper two (or more if its taller) tiles are just overheard combos. Technically, you could use layers for this too, and you might want to, depending on the tile set.
The direct warp is going to take you to an identical screen with the following conditions: All geyser tiles are now 'fast' up conveyors. You can put either solid combos, or direct warp combos on the sides of the geyser, if Link 'falls out'. You can use either one depending on if you want link to be forced to ride to the top before jumping off, or, if you want him to be able to jump out half way up. It's up to you really. This screen will require two warps if you use the non-solid combos on the side. The warps to the side will take you to a 'falling' screen, and the warp at the top will take you to a "top" screen. Let me explain.
The "falling screen" is simple enough in concept. It's a non solid copy of the room with side view gravity. This can be done by copying the screen to another location, and using it as a layer, and checking "use layer X as background" You'll want to copy the screen instead of using it directly cause you will need different geyser combos. Make an outline of solid combos around the geyser. Leave one tile width between the geyser, and invisible solid combo. Now, at the bottom of the geyser, place direct warps that send Link to the original, base screen (the one Link will enter, and exit from in the actual dungeon).
Now, the top screen if our fourth, and final copy of the screen. You have a bit more freedom with this, depending on how you would have these set up. But basically, all this screen does it have a regular tile at the top position of the geyser where link can stand, and you will place direct warps, solid combos, or walk able combos around the top of the geyser with regards to how you want Link to move around. I,e, lets say we have a standalone geyser in a room. at the top, link might just be surrounded by four direct warps to the falling screen. Now, if this geyser leads somewhere then maybe it would be three warps, and a walkable combo. You might want to use another direct warp to take link to the original screen, if the geyser was to move him through the room.
I hope this made sense, I typed it up really fast. I'll probably test it out later, and post some screens, or something, and see if it even works