So if I want to custom install (like I did with the version before this one) I should download the offline package, uninstall then custom install? Just want to make sure. Thanks.
Essentially yes.
However, since there aren't any major changes, newly added components, but some changes, then you could get away with doing a program update from the avastUI as it should honour your existing settings and components.
I appreciate if you want to make sure, yes do the custom install, but if you choose to do that don't uninstall your existing avast version or you could lose some of your settings. You can of course Backup your settings and then Restore settings.