File size is huge, yeah, but this has a lot of features and a good design, so it still warrants use instead of resorting to Filezilla for example.
Its install procedure wasn’t detected by my install logger, so it’s unclear how many files or registry entries were created in the process.
License key activated without issue for me. It says this is a Lifetime license, and while that’s technically true, this license also gives you 1 year of free updates (as I found mentioned in the settings of the app), a neat detail that is not being specified elsewhere.