One suggestion: Read the rule again, you misunderstand some. All three point is including in the pdf.
Sorry I haven't directly answer the question. Because English is not my first language. So I'm afraid I read it wrong. And I also not good at explain it to other people.
Now you ask, I could provide my understanding. Maybe not correct, read it with the rule pdf.
1. Yes but not exactly right. Gates only reclaim by use. When the gate got use it go to their place. Color one return to the corresponding player with same color. Neutral gate return to share pool and moved player can reclaim to own 4 Neutral gate.
2. It won't be infinite loops. Because the gate use once then it will go out of the board, so player can't pass through it twice. So no loop.
3. The "no single portalling" is to prevent player to just use the gate to move one step again and again, because one step move reduces the strategy of the game. This game is not like most game to think about your next step. You need to think about multi steps and build the road to the target, and you can only place the last gate in front of you. And you also need to prevent other player used your road(because gate only used once, if other player use it, you lose your road). For example you use the red player, just want to make a two step move, you place the first gate, the blue player can use a blue gate to block your road. That is the strategy point. If allow one step move, player can use always move one step, other player make no strategy to prevent it.
Ohhh, because each gate gets removed as you travel through it, you can never travel through the same gate twice. Thanks!
I still think that gates automatically going to the player of the same color is weird. Could a player end up with too many neutral gates and not be able to pick up those gates? Is it impossible to pick up a gate of the opposite color?