There has been a problem with people getting stuck at the front gate that will ruin your park. It took me a while to figure out what was causing this bug... but this is the cause. This is what this bug causes to happen-





No one will enter the park... you will eventually fail because you are not getting revenue and everyone that is in the park will leave within a matter of months. It is a sad story all around. If you notice this happening immediately pause the game. look around at your rides and make sure every one has white entrance and exit gates at them. if they are missing rebuild the paths that connect the ride to the main path. Notice in these images how the first coaster has white gates and the second one does not-




In some cases I have had several rides end up this way.. either after a save or just randomly. I am not sure why but it does fix the front gate. I hope this helps you guys because it took me a long time to figure out and it will instantly break your park.