This is a category of Fixlets which install programs or files.
There are install Fixlets which require you to download the software, upload it to your TEM server, and then change the beginning of the ActionScript to reflect your particular server.
There are install Fixlets which download the software directly from the provider. This type requires the endpoint to have an internet connection, and for the 3rd party server to be online, and for the download to still be available. The advantage to this approach is no actionscript modification is needed for use on any TEM server and the files do not take up TEM server storage. The disadvantage is that this method is prone to failure.
Either type of install Fixlet can be turned into the other in most cases.
Examples are a good guide in how to create a similar Fixlet. If the software your trying to install uses an MSI, then any example MSI Install Fixlet should provide a helpful guide. The same goes for Windows Update, Inno Setup, InstallShield, and other installer types.
Here are some helpful links to command line switches for different installer types: