I just checked my one-week-old hives today, and they were building their comb on only one side of the hive (about 20 - 30cm of 40 cm bar) as well as the comb touching the rear edge of the 3cm bars by bar 6, so i've got some 8mm spacers in there now between 5-6 and 6-7. I also turned bar 3 and 5 around so they're on the other side. It's been quite hot here for the start of spring so I hope they'll be fine with that move. I guess I'll take another peek in two days just to check.
I can see that top bar hives are a work in progress. Quite fun though!