I have a done two fresh installs and both give the same issue;
owncloud installed current ver. and onlyoffice installed current ver.
and the onlyoffice works for about 24 hours and then just stops ( you see it download the file rather than openit in only office.
- workaround = go to settings > advanced > push ‘save’.
*Notes - I think there might be a scheduled task that checks the connector and its check fails for some reason and it disables/off-lines the connector.