Cooperation of Box and Salesforce

Thank you for your patronage.
About link of Salesforce and Box, it is an inquiry.
【Request】
The file which was stored away in Salesforce.
It wants to cooperate in BOX.
【Inquiry contents】
I install "Box for Salesforce",In using Salesforce Developer Toolkit,
I recognize that the above, realization of 【Request】 are possible.I made the cord sample of mention on the Salesforce side in the following link,
It is not movement to expect.A file is the situation that it is not cooperated on the Box side.
https://ja.developer.box.com/guides/tooling/salesforce-toolkit/samples/
In carrying out cooperation of Box from Salesforce,When the Box side has some setting becoming required, I recognize it,
I do not know what setting is necessary for the Box side.
I want you to tell me about this.
※I recognize the point that must make ServiceAccount.
In addition, please point it out if there is the recognition disagreement including the mention contents mentioned above.
Then, I would like it