Sisulizer setup (Sisu.exe) installs Hunspell spell checker engine (hunspelldll.dll) into Sisulizer directory (e.g. C:\Program files (x86)\Sisulizer 4). If engine file is not installed on Sisulizer directory you need to run Sisulizer setup again. Uninstall your current Sisulizer, remove the directory and run setup again. OpenOffice uses Hunspell spell checker.
In addition of the engine file Hunspell needs dictionary files as well. Dictionary file extensions are .dic and .aff. Each language has both .dic and .aff files. Sisulizer setup does not install any dictionary files but you have to download and install them. You can have dictionaries for more than 50 different languages. You have two choices.
OpenOffice 3.0 dictionaries are deployed as single .oxt file. This file contains dictionary, hyphenation and thesaurus files of one language. The file is actually a ZIP file. You can either extract the files manually and add .dic file into Sisulizer, or you can just add .oxt file and let Sisulizer to extract the dictionary files for you. Download a dictionary file. Choose Tools | General menu, select Spelling & Grammar sheet, and click Add button.
If you have OpenOffice installed you already have several .oxt files installed on your computer. Look at C:\Program Files\OpenOffice.org 3\share\extension\install directory for dictionary files.
OpenOffice 2.x dictionaries are deployed as ZIP files that contain .dic and .aff files. Download a dictionary file, unzip it and add the .dic file to Sisulizer. Choose Tools | General menu, select Spelling & Grammar sheet, and click Add button.