The reversing of the map direction and the monster chasing the players is currently not possible to create. The community is craving for this feature a long time, but there was no feedback from the devs, if they will add it in the future. I suggest that the maps were created with an alternative program and there might be some problems to implement them in the editor.

The event with the water is quite simple to create. First you need your water prop. That can either be a plane water surface as prop (search for water in the asset list) or you create an empty object (right click on empty hierarchy space and then click on "create empty") and then click on "Add Component" and after that the "Rendering" option. In the next menu at the bottom the water option should be available. With that you have an animated moving water surface and can adjust the wave height, speed and even the colour.
Either way, you need to rename the water prop to find it easily later.

In the custom space option, you could create an animation with the water surface. For example, if you want it to rise, simply use the "Play Tween Animation" option and click on advanced option. With add element you can select a specific prop that should be animated. Select your object and add the coordinates you want it to move (you can find that in detail in my guide on custom spaces here in steam: Custom board spaces guide).

To add damage on multiple spaces, use the damage player action and choose advanced. There you can select all the spaces you want to deal damage to. I recommend renaming these spaces as well to be sure which one you select.
But this event won't stay for a certain amount of time. It is just for the single event.

If you have further questions on the editor, you might want to join the following steam group in which I try to gather mod creators for helping each other:

Pummel Party Modding Community

Thank u Very Much for answwer!!!!!!!!!