Yes, we understand the problem. We have dedicated personnel that deals with false positives and regularly sends reports to a/v companies.
Currently, we are aware only of the AVG problem and we are already trying to contact them and resolve this issue. There haven't been reports about Avast and VirusTotal reports show that Avast detection is clean. Do you have any screenshots of Avast's detections?
P.S. I will move this topic to the Antivirus sub-forum.
Another way to go would be using the callback/reverse connection. This is also a direct connection type, only in this case it is the Viewer that should be accessible externally rather than the Host (that's why it's "reverse"). Might not be an option if you travel often though with the laptop where the Viewer is installed.
Answering your question regarding where RU Server should/can be installed - it is highly recommended that RU Server is "stationary" , that is it is a dedicated computer with a static IP address, or a DNS name, running 24/7. Perhaps, it's an overkill for just accessing a single computer.
If you experience issues with speed/performance, you may try tweaking some settings. This article may help.
He knows I placed RUT on his computer but sometimes he wants to clean up his computer and does not follow the 'rules' for doing so and he just removes the folders fr om 'Program Files'.
This is a bad way to clean up a PC. While there's no harm to delete traces of programs you no longer use, there's equally no harm NOT to delete everything in one's Program Files folder unless one desperately needs free disk space.
I put a shortcut on the desktop to start and stop the service, so only when he starts the service the connection is possible.
You can use Agent instead of Host then, if you only need unattended access. Perhaps, your brother-in-law deletes the Host because he doesn't like the idea of unattended access (which the Host provides). If you use Agent instead of Host and assure him that it's only when the Agent is running that you have access to his PC, perhaps he won't be deleting anything.
A good practice is to download Agent right on the desktop and run it from there. If the program isn't deleted after use, the ID and password stay the same, so you won't have to update the corresponding record in your Viewer address book.