The downloaded .oxt file is a zip archive. If you are
creating a new dictionary, copy the .aff and
.dic files from this archive in the spell
subfolder of the Oxygen XML Editor preferences folder.
The Oxygen XML Editor preferences folder is [APPLICATION-DATA-FOLDER]/com.oxygenxml>, where
C:\Users\[USER-NAME]\AppData\Roaming on Windows Vista/7/8/10
[USER-HOME-FOLDER]/Library/Preferences on OS X
[USER-HOME-FOLDER] on Linux
If you are updating an existing dictionary, copy the .aff and
.dic files into the folder
Restart the application after copying the dictionary files.
Note: You can specify that Oxygen XML Editor includes dictionaries and term lists
from a custom location by selecting the Include dictionaries and term list
from option and specifying its path in the
Dictionaries preferences page.