1.) Disable the "Download" button until at least one application is selected. After all you can not "Download" anything if you did not choose any applications. Duh!
2.) Please show download speed (perhaps text to download percentage).
3.) When a download fails you get "Unable to connect to the remote server" and then "Download aborted".
Not a very helpful error. Why not tell the user which one has failed? And perhaps ask user if user wishes to continue anyways.
Thus, it should be treated as a "warning" not an "error".
4.) Why download something if it has not changed since last download?
Perhaps perform a simple MD5 check and if file has not changed do not download.
So perhaps make it optional. Perhaps an option of "Only Download New Files". Something like that...
When done tell user which files where not downloaded since they where not new.
5.) Downloading the files is nice, but a scheduler would be of more helpful.
Also, would be nice if you could start installing the applications directly via the GUI some how.
Perhaps right click on an entry and "Install". While your at it, how about have "Remove", "Rename", etc. too.
6.) Stop calling home (188.8.131.52) or at least make "Check for Updates" optional.
I assume that is what it's doing?
Oh my, a nasty experience if you don't let it call home via firewall.
Another "Unable to connect to the remote server" error and then it attempts to crash with "InvalidArgument=Value of '3' is not valid for 'SelectedIndex'.
Parameter name: SelectedIndex".
7.) Save user settings (which package is selected for example and of course remember "Custom") either via registry if using installer or via a ini file if using zip package.