I just tried the Light version of this game, and I could see the line perfectly fine. Is there anything that you changed between the demo and full version that could have caused this problem?
I like how some of the comments about the line being invisible are being down-rated while others are being up-rated. Yes, the line is invisible (permanently for some and temporarily for others) for some people. And no, just because the glitch doesn't show up for you doesn't mean it doesn't show up for others. This game is pretty much unplayable for me and I would really appreciate it if the glitch was fixed so that people experiencing this could actually try out the game.
Auto-joining is broken...
This is the only easy badge standing in my way, and the other badges are also there to consider. No workarounds have worked either. I hate to say it, but this game probably needs a removal.
Caesary and Battalion Arena badges are still in Badge Master even though the badges were removed from the badge list. Please remove them or find a workaround.
It's fun to get a huge 5-star hotel, then destroy all the elevators and receptions to strand them all on high floors ;). They start running in the same direction after you delete everything. Somehow, I lost like 30 people (must have jumped out the windows).
Trying to keep the bowling lanes up to their standards is impossible. I can build like 5 and 3 will be empty, leaving the other 2 with like 20 people each at once >.>.
@Dimensionless
I have commented about this problem before, but according to your comment, it wasn't fixed :(. Judging by this, it probably won't be changed anytime soon :P. Oh well.