Are you talking specifically about downloads that don't complete, then say "Connection Interrupted"? This is a known issue in T:ANE andTRS19 for large assets over 1MB or so without FCT. In T:ANE, the asset downloads but then there is a bug in the completion process, and it fails to complete. If you right-click the asset again and choose "Download", it will usually just install right away because it actually has it there. Unfortunately, not so inTRS19. Earlier, it used to throw that error and the only choice was to start another long download, but then it would complete OK. Recently (TRS19 SP5?) I have noticed that instead of throwing the error, it just starts the download over again automatically, so it just takes twice as long as it should. Maybe it is just me, because I seem to be the only one that complains about it, but this is the way that I have found it works for me. I have also posted these tips multiple times, so there have been others with this issue.
If you do try the DLS, MSGSapper and Dangavel have created some very good desert plants.