Is this allowed, or out of staying on track rule:
1. I had never stopped to think about that;
2. My rules actually do not say cork undersides are part of the track proper;
2. Weren't it for this observation I'd never hesitate about having it as valid;
3. In fact, I thought of that trick during the design;
4. No OWOOT competition so far outlawed it (I looked for and found an IRC example for reference);
5. It seems pointless to add an annoying restriction on such a small thing that may just be a graphical design oversight;6. Therefore I'm allowing it.
7. It took only a really short while for me to get knocked off my high horse on the subject of my "perfect" rule set, and the long excuses above are here just for making that all the more obvious
Can I enter corkscrew left/right in both ways or just as shown with green arrow?
I assume you're asking whether you need to follow the yellow line strictly (green line) or only start to "loop" the cork halfway through it (red line). If so, both lines are valid, as long as you get upside down and leave by the other side of the red wall.