Uuuuhm.

You run cygwin, a linux-emulator on windows, to run postgres.
Now you want to run wine, to run windows, to run postgres.

Well - for having only one database, which needn't be synchronized, I can understand...
I don't know whether the dataformat of both can be shared - perhaps you read something on the postgresql - website.
Or make a backup of the data, install the linux-postgresql-db, preferably the same version (number), and try to give as data-dir argument the mounted windows-partition, cygwin-postgresql datadir.