No. Spplice is entirely open-source software. However, the Windows installer may get falsely flagged as a virus.
Its source code is available on GitHub, along with an alternative download that's much less likely to get flagged as a
virus.
The reason that some virus scans might detect Spplice's Windows installer as one is because of two things. Firstly, it
is an unsigned application. This is what causes Windows's SmartScreen to pop up when you first run the installer. This
is the case for most applications downloaded from the web, unless the developer has paid a hefty annual fee to secure
a Microsoft licence.
The installer is built on NSIS, or the Nullsoft Scriptable Install System, which is yet another open source system
commonly used to create Windows installers. But to package everything into one neat ".exe" file, it has to awkwardly
extract files from itself, as well as download some additional setup files. Obviously, this is exactly what an installer
should do and is typically harmless. But coincidentally, viruses tend to do the same thing. This is why some
anti-virus software cannot tell the difference if the program is unsigned.
This issue is usually caused by having Unicode (special, non-latin) characters in either your Windows username or the Spplice, Steam, or Portal 2 installation paths. Unfortunately, this is an issue deeply rooted within Neutralino - the framework that Spplice runs on. The best way to fix this is to create a new user account. If the program folders contain Unicode characters, it is probably best to reinstall them to a new folder.
Unfortunately, we cannot predict the cause for every error. If we could, there wouldn't be any errors to begin with.
We can, however, provide some basic steps you can take to troubleshoot some common issues.
Firstly, please note that Spplice is currently only officially supported on Windows 10 and Linux. Older Windows
versions might be capable of starting Spplice, but they lack the command line tools required to extract Spplice
packages. This might change in the future, but please understand that as of now we can not and will not try to help
your system run Spplice on unsupported Windows versions. And while we do provide a download for MacOS users, it has
never been properly tested, and as such providing support is difficult.
The first step in debugging is a simple system reboot. It sounds simple, but can fix many issues. If that didn't work
(and if you're on Windows), try running Spplice as Administrator.
If all else fails, you can get more hands-on help through the #tech-support channel in the
PortalRunner Community Discord server.
First, make sure Portal 2 is not already open. Spplice expects Portal 2 to be closed when it starts up. You may also try
closing or opening Steam before running Spplice. Theoretically this shouldn't matter, but it's worth a shot.
If none of that worked, your best bet is to go through the general troubleshooting steps mentioned in the section above.