On some maps the platforms slightly overlap each other. So to avoid players standing on them the devs made them into ice platforms. So they act like normal ice. The same goes for the top of some towers. They will have ice on them so you can gain momentum.

The software Losi suggested will work just fine. There is also a guide on how to use xmouse button control on the discord server. It's the one I use, and it works well for me.

I haven't seen Sebban active for quite a while, so it might be worth getting at least one more mod to speed things up.

managed to miss that myself, whoopsie