Restore single database from full backup...

I know this question has been asked before but I still have little idea of how to go about this. Perhaps someone might be kind enough to offer a step-by-step guide?
I regulary backed up the results of running the command xtrabackup --backup --target-dir=/var/sqlback on my ubuntu 14.04 server to a cloud storage facility.
I am now in a position where I want to restore a single database to the server from my Windows PC.
It is prohibitively slow (and frustrated by time-outs) trying to download all the data from the cloud service to my PC but I have managed to download the database directory (containing only .frm files) and the mysql data root contents (massive ibdata1 plus some xtrabackup files and a vackup-my.cnf file)

Is it possible to restore this single database from these files? I have no idea how it would work… I cannot prepare files on the windows PC as it does not support xtrabackup AFAIK and I would like to keep the current database files on the linux server (ideally copying the existing database to be replaced first).

Any tips or hints?

Many Thanks

update - Have now downloaded the whole contents of the data directory. Replaced current data dir on my local windows mysql installation and started up mysql but the database still has empty tables. Tried starting up with innodb_force_recovery =6 which reported that the tables had frm files but could not open tables from internal innodb data dictionary. Am unable to run xtrabackup prepare as windows doesn’t support xtrabackup (found an old windows alpha version but it didn’t do anything but produce error messages wehn i tried running it).
Pretty stuck… Bit frustrating knowing I have all the pieces but am unable to put it back together…