Opening files Error -36
I had this problem recently and it was due to a problem with the previous version of macOS Sierra supported by acknowledgement by Apple of many similar reported bug in version 10.12.2.

The most recent update to macOS Sierra 10.12.3 resolved the error -36 with previewing files on the Time Capsule for me, try updating. 

Dot_clean did not work for me but connecting the TC via SMB was a simple workaround until Apple sorted the issue out.