This:
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Step one:Need to clips of water, soil or air. Like this:
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Step two:Add a road together water on this tutorial i used "StadiumRoadTiltStraighth", now should look like this:
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Step three:In my case using the "TrackStudio" add two blocks "StadiumWaterClip"
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Step four:Change the Variation of the two newly added blocks and Rotate two blocks below:
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Step five: Mix the two blocks with the top down, Like this:
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See the result.
Warning not delete 2 roads on laterals, because if you delete it when open track again the bug finalroad miss.
I hope the tutorial is very clear and easy, and wish you all Merry Christmas.
Flaix