OpenOffice install and use on Synology (DS1821+)

Whilst i and family regulary use either SMB or Synology Drive to access MS Office docs, we awant to be able to edit them in a cloud type manner (ie broswer) when either on devices that dont have office or not able to connect to Network NAS resides on (either VPN or Unify Travel Router).

Have therefore been looking at possibility of using OpenOffice, given that Synology office necessitates converting, which dont want to do as still want to access via MS Office clients.

But in installing/using OpenOffice i then also want to ensure we LDAP user security access/priv/rights.

Reverse proxy is it an option and can be setup to ensure a logon page is presented on internet connection?

Will have seen you reverse Proxy tutorial, but could you consider doing this with a real world example of an an (docker) like OpenOffice?

So to summarise want to edit MS Office docs; maintain their file format; edit offline (via browser); maintain synology security on users via LDAP

Any ideas/better ideas