The Japanese Renewable Energy Foundation has published results of a survey of companies building solar projects in Japan, and this article at Yahoo describes them. Thanks to this tweet by Tetsunari Iida for the link.
The Japanese system uses the concept of a contract between the solar owner and the utility, instead an obligation by law (as the German system does). This is a clear failure causing unnecessary costs and delays, and even completely derailing some projects.
As a consequence, many projects are forced to spend up to half a year to negotiate contracts. And some utilities even refuse to buy renewable electricity, with various excuses. This obviously has to change. It is an inefficient way of running things. The conditions for selling under the feed-in tariff need to be set finally by law, and there should be no loopholes and excuses for refusing to buy.