I took the liberty to split this post out of the original thread, as posts there became more off topic.
You may need to open the package(s) (menu package > open packag file) from components/synspellchecker/* first.
I have to check, it may miss the "auto known by IDE" part.
Once it had been open, it can be selected in the "package install/uninstall" dialog"
You do need the aspell library on your system.
You can configure the path in the options, if it is not in a location were it is found automatically.
You will need to go the the color config, and edit the color.