Avast corrected it. I can now download and install the software again.
Let me explain:
False positive is a common term in spam and virus detection. It means that was false to flag it as a positive.
They flag this kind of software as a trojan, maybe because the download exe contacts the web server to download the rest of the software.
So this has nothing to do with this specific software, nor something bad was added, this is just a common modus operandi, so anti-virus flag the suspicious download action.
Hope it’s clear now. It’s a ongoing battle to make anti-virus software houses to remove these alerts from honest software.